Multi-speed planetary transmissions with three interconnected gear sets

ABSTRACT

The family of transmissions has a plurality of members that can be utilized in powertrains to provide at least seven forward speed ratios and one reverse speed ratio. The transmission family members include three planetary gear sets having six torque-transmitting mechanisms and a fixed interconnection. Also, one planetary gear member is continuously connected with the transmission housing. The powertrain includes an engine and torque converter that is continuously connected to at least one of the planetary gear members and an output member that is continuously connected with at least one of the planetary gear members. The six torque-transmitting mechanisms provide interconnections between various gear members, the fixed interconnection, the input shaft, the output shaft, and the transmission housing, and are operated in combinations of two to establish at least seven forward speed ratios and at least one reverse speed ratio.

TECHNICAL FIELD

[0001] The present invention relates to a family of power transmissionshaving three planetary gear sets that are controlled by sixtorque-transmitting devices to provide at least seven forward speedratios and one reverse speed ratio.

BACKGROUND OF THE INVENTION

[0002] Passenger vehicles include a powertrain that is comprised of anengine, multi-speed transmission, and a differential or final drive. Themulti-speed transmission increases the overall operating range of thevehicle by permitting the engine to operate through its torque range anumber of times. The number of forward speed ratios that are availablein the transmission determines the number of times the engine torquerange is repeated. Early automatic transmissions had two speed ranges.This severely limited the overall speed range of the vehicle andtherefore required a relatively large engine that could produce a widespeed and torque range. This resulted in the engine operating at aspecific fuel consumption point during cruising, other than the mostefficient point. Therefore, manually-shifted (countershafttransmissions) were the most popular.

[0003] With the advent of three- and four-speed automatic transmissions,the automatic shifting (planetary gear) transmission increased inpopularity with the motoring public. These transmissions improved theoperating performance and fuel economy of the vehicle. The increasednumber of speed ratios reduces the step size between ratios andtherefore improves the shift quality of the transmission by making theratio interchanges substantially imperceptible to the operator undernormal vehicle acceleration.

[0004] It has been suggested that the number of forward speed ratios beincreased to six or more. Six-speed transmissions are disclosed in U.S.Pat. No. 4,070,927 issued to Polak on Jan. 31, 1978; U.S. Pat. No.6,071,208 issued to Koivunen on Jun. 6, 2000; U.S. Pat. No. 5,106,352issued to Lepelletier on Apr. 21, 1992; and U.S. Pat. No. 5,599,251issued to Beim and McCarrick on Feb. 4, 1997.

[0005] Six-speed transmissions offer several advantages over four- andfive-speed transmissions, including improved vehicle acceleration andimproved fuel economy. While many trucks employ power transmissions,such as Polak, having six or more forward speed ratios, passenger carsare still manufactured with three- and four-speed automatictransmissions and relatively few five or six-speed devices due to thesize and complexity of these transmissions. The Polak transmissionprovides six forward speed ratios with three planetary gear sets, twoclutches, and three brakes. The Koivunen and Beim patents utilize sixtorque-transmitting devices including four brakes and two clutches toestablish six forward speed ratios and a reverse ratio. The Lepelletierpatent employs three planetary gear sets, three clutches and two brakesto provide six forward speeds. One of the planetary gear sets ispositioned and operated to establish two fixed speed input members forthe remaining two planetary gear sets.

[0006] Seven-speed transmissions are disclosed in U.S. Pat. Nos.4,709,594 to Maeda; 6,053,839 to Baldwin et. al.; and 6,083,135 toBaldwin et al. Seven- and eight-speed transmissions provide furtherimprovements in acceleration and fuel economy over six-speedtransmissions. However, like the six-speed transmissions discussedabove, the development of seven- and eight-speed transmissions has beenprecluded because of complexity, size and cost.

SUMMARY OF THE INVENTION

[0007] It is an object of the present invention to provide an improvedfamily of transmissions having three planetary gear sets controlled toprovide at least seven forward speed ratios and one reverse speed ratio.

[0008] In one aspect of the present invention, the family oftransmissions has three planetary gear sets, each of which includes afirst, second and third member, which members may comprise a sun gear, aring gear, or a planet carrier assembly member.

[0009] In referring to the first, second and third gear sets in thisdescription and in the claims, these sets may be counted “first” to“third” in any order in the drawings (i.e., left to right, right toleft, etc.).

[0010] In another aspect of the present invention, each of the planetarygear sets may be of the single pinion-type or of the double pinion-type.

[0011] In yet another aspect of the present invention, the first memberof the first planetary gear set is continuously interconnected to thefirst member of the second planetary gear set and the first member ofthe third planetary gear set through an interconnecting member.

[0012] In yet another aspect of the present invention, the second memberof the first planetary gear set is continuously interconnected with astationary member (transmission housing).

[0013] In yet a further aspect of the invention, each family memberincorporates an input shaft which is continuously connected with amember of the planetary gear sets and an output shaft which iscontinuously connected with another member of the planetary gear sets.

[0014] In still a further aspect of the invention, a firsttorque-transmitting mechanism, such as a clutch, selectivelyinterconnects a member of the first planetary gear set or theinterconnecting member with the input shaft, the output shaft, or amember of the second or third planetary gear set.

[0015] In another aspect of the invention, a second torque-transmittingmechanism, such as a clutch, selectively interconnects a member of thesecond planetary gear set or the interconnecting member with the inputshaft, the output shaft or a member of the first or third planetary gearset.

[0016] In a still further aspect of the invention, a thirdtorque-transmitting mechanism, such as a clutch, selectivelyinterconnects a member of the third planetary gear set or theinterconnecting member with the input shaft, the output shaft, or amember of the first or second planetary gear set.

[0017] In a still further aspect of the invention, a fourthtorque-transmitting mechanism, such as a clutch, selectivelyinterconnects a member of the first, second or third planetary gear setwith another member of the first, second or third planetary gear set.Alternatively, the fourth torque-transmitting mechanism, such as abrake, selectively connects a member of the first, second of thirdplanetary gear set with a stationary member.

[0018] In a still further aspect of the invention, a fifthtorque-transmitting mechanism, such as a clutch, selectivelyinterconnects a member of the second or third planetary gear set or theinterconnecting member with another member of the first, second or thirdplanetary gear set. Alternatively, the fifth torque-transmittingmechanism, such as a brake, selectively connects a member of the first,second or third planetary gear set with the stationary member.

[0019] In still another aspect of the invention, a sixthtorque-transmitting mechanism, such as a clutch, selectivelyinterconnects a member of the first, second or third planetary gear setor the interconnecting member with another member of the first, secondor third planetary gear set. Alternatively, the sixthtorque-transmitting mechanism, such as a brake, selectively connects amember of the first, second or third planetary gear set with thestationary member.

[0020] In still another aspect of the invention, the sixtorque-transmitting mechanisms are selectively engageable incombinations of two to yield at least seven forward speed ratios and atleast one reverse speed ratio.

[0021] The above object and other objects, features, and advantages ofthe present invention are readily apparent from the following detaileddescription of the best modes for carrying out the invention when takenin connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022]FIG. 1a is a schematic representation of a powertrain including aplanetary transmission incorporating a family member of the presentinvention;

[0023]FIG. 1b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 1a;

[0024]FIG. 2a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0025]FIG. 2b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 2a;

[0026]FIG. 3a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0027]FIG. 3b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 3a;

[0028]FIG. 4a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0029]FIG. 4b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 4a;

[0030]FIG. 5a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0031]FIG. 5b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 5a;

[0032]FIG. 6a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0033]FIG. 6b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 6a;

[0034]FIG. 7a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0035]FIG. 7b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 7a;

[0036]FIG. 8a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0037]FIG. 8b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 8a;

[0038]FIG. 9a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0039]FIG. 9b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 9a;

[0040]FIG. 10a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0041]FIG. 10b is a truth table and chart depicting some of theoperating characteristics of the powertrain shown in FIG. 10a;

[0042]FIG. 11a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0043]FIG. 11b is a truth table and chart depicting some of theoperating characteristics of the powertrain shown in FIG. 11a;

[0044]FIG. 12a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0045]FIG. 12b is a truth table and chart depicting some of theoperating characteristics of the powertrain shown in FIG. 12a;

[0046]FIG. 13a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0047]FIG. 13b is a truth table and chart depicting some of theoperating characteristics of the powertrain shown in FIG. 13a;

[0048]FIG. 14a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0049]FIG. 14b is a truth table and chart depicting some of theoperating characteristics of the powertrain shown in FIG. 14a;

[0050]FIG. 15a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0051]FIG. 15b is a truth table and chart depicting some of theoperating characteristics of the powertrain shown in FIG. 15a;

[0052]FIG. 16a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0053]FIG. 16b is a truth table and chart depicting some of theoperating characteristics of the powertrain shown in FIG. 16a;

[0054]FIG. 17a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0055]FIG. 17b is a truth table and chart depicting some of theoperating characteristics of the powertrain shown in FIG. 17a;

[0056]FIG. 18a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention; and

[0057]FIG. 18b is a truth table and chart depicting some of theoperating characteristics of the powertrain shown in FIG. 18a.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0058] Referring to the drawings, wherein like characters represent thesame or corresponding parts throughout the several views, there is shownin FIG. 1a a powertrain 10 having a conventional engine and torqueconverter 12, a planetary transmission 14, and a conventional finaldrive mechanism 16.

[0059] The planetary transmission 14 includes an input shaft 17continuously connected with the engine and torque converter 12, aplanetary gear arrangement 18, and an output shaft 19 continuouslyconnected with the final drive mechanism 16. The planetary geararrangement 18 includes three planetary gear sets 20, 30 and 40.

[0060] The planetary gear set 20 includes a sun gear member 22, a ringgear member 24, and a planet carrier assembly 26. The planet carrierassembly 26 includes a plurality of pinion gears 27 rotatably mounted ona carrier member 29 and disposed in meshing relationship with both thesun gear member 22 and the ring gear member 24.

[0061] The planetary gear set 30 includes a sun gear member 32, a ringgear member 34, and a planet carrier assembly member 36. The planetcarrier assembly member 36 includes a plurality of pinion gears 37rotatably mounted on a carrier member 39 and disposed in meshingrelationship with both the sun gear member 32 and the ring gear member34.

[0062] The planetary gear set 40 includes a sun gear member 42, a ringgear member 44, and a planet carrier assembly member 46. The planetcarrier assembly member 46 includes a plurality of pinion gears 47rotatably mounted on a carrier member 49 and disposed in meshingrelationship with both the sun gear member 42 and the ring gear member44.

[0063] The planetary gear arrangement also includes sixtorque-transmitting mechanisms 50, 52, 54, 56, 58 and 59. Thetorque-transmitting mechanisms 50, 52, 54 and 56 are rotating-typetorque-transmitting mechanisms, commonly termed clutches. Thetorque-transmitting mechanisms 58 and 59 are stationary-typetorque-transmitting mechanisms, commonly termed brakes or reactionclutches.

[0064] The input shaft 17 is continuously connected with the sun gearmember 42, and the output shaft 19 is continuously connected with thering gear member 34. The sun gear member 22 is continuously connectedwith the transmission housing 60. The planet carrier assembly member 26is continuously connected with the sun gear member 32 and with the ringgear member 44 through the interconnecting member 70.

[0065] The ring gear member 24 is selectively connectable with theplanet carrier assembly member 46 through the clutch 50. The ring gearmember 24 is selectively connectable with the sun gear member 42 throughthe clutch 52. The planet carrier assembly member 36 is selectivelyconnectable with the planet carrier assembly member 46 through theclutch 54. The planet carrier assembly member 36 is selectivelyconnectable with the sun gear member 42 through the clutch 56. Theplanet carrier assembly member 26 is selectively connectable with thetransmission housing 60 through the brake 58. The planet carrierassembly member 36 is selectively connectable with the transmissionhousing 60 through the brake 59.

[0066] As shown in FIG. 1b, and in particular the truth table disclosedtherein, the torque-transmitting mechanisms are selectively engaged incombinations of two to provide eight forward speed ratios and a reversespeed ratio.

[0067] The reverse speed ratio is established with the engagement of theclutch 52 and the brake 59. The clutch 52 connects the ring gear member24 with the sun gear member 42. The brake 59 connects the planet carrierassembly member 36 with the transmission housing 60. The sun gear member22 does not rotate. The planet carrier assembly member 26 rotates at thesame speed as the sun gear member 32 and the ring gear member 44. Thering gear member 24 and sun gear member 42 rotate at the same speed asthe input shaft 17. The planet carrier assembly member 26 rotates at aspeed determined from the speed of the ring gear member 24 and the ringgear/sun gear tooth ratio of the planetary gear set 20. The planetcarrier assembly member 36 does not rotate. The ring gear member 34rotates at the same speed as the output shaft 19. The ring gear member34, and therefore the output shaft 19, rotates at a speed determinedfrom the speed of the sun gear member 32 and the ring gear/sun geartooth ratio of the planetary gear set 30. The numerical value of thereverse speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 20 and 30.

[0068] The first forward speed ratio is established with the engagementof the clutch 54 and the brake 59. The clutch 54 connects the planetcarrier assembly member 36 to the planet carrier assembly member 46. Thebrake 59 connects the planet carrier assembly member 36 to thetransmission housing 60. The sun gear member 22 does not rotate. Theplanet carrier assembly member 26 rotates at the same speed as the sungear member 32 and the ring gear member 44. The planet carrier assemblymembers 36 and 46 do not rotate. The ring gear member 34 rotates at thesame speed as the output shaft 19. The ring gear member 34, andtherefore the output shaft 19, rotates at a speed determined from thespeed of the sun gear member 32 and the ring gear/sun gear tooth ratioof the planetary gear set 30. The sun gear member 42 rotates at the samespeed as the input shaft 17. The ring gear member 44 rotates at a speeddetermined from the speed of the sun gear member 42 and the ringgear/sun gear tooth ratio of the planetary gear set 40. The numericalvalue of the first forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 30 and 40.

[0069] The second forward speed ratio is established with the engagementof the clutch 54 and the brake 58. The clutch 54 connects the planetcarrier assembly member 36 to the planet carrier assembly member planetcarrier assembly member 46. The brake 58 connects the planet carrierassembly member 26 to the transmission housing 60. The planetary gearset 20, sun gear member 32 and ring gear member 44 do not rotate. Theplanet carrier assembly member 36 rotates at the same speed as theplanet carrier assembly member 46. The ring gear member 34 rotates atthe same speed as the output shaft 19. The ring gear member 34, andtherefore the output shaft 19, rotates at a speed determined from thespeed of the planet carrier assembly member 36 and the ring gear/sungear tooth ratio of the planetary gear set 30. The sun gear member 42rotates at the same speed as the input shaft 17. The planet carrierassembly member 46 rotates at a speed determined from the speed of thesun gear member 42 and the ring gear/sun gear tooth ratio of theplanetary gear set 40. The numerical value of the second forward speedratio is determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 30 and 40.

[0070] The third forward speed ratio is established with the engagementof the clutches 50 and 54. The clutch 50 connects the ring gear member24 to the planet carrier assembly member 46. The clutch 54 connects theplanet carrier assembly member 36 to the planet carrier assembly member46. The sun gear member 22 does not rotate. The planet carrier assemblymember 26 rotates at the same speed as the sun gear member 32 and thering gear member 44. The ring gear member 24 rotates at the same speedas the planet carrier assembly members 36 and 46. The planet carrierassembly member 26 rotates at a speed determined from the speed of thering gear member 24 and the ring gear/sun gear tooth ratio of theplanetary gear set 20. The ring gear member 34 rotates at the same speedas the output shaft 19. The ring gear member 34, and therefore theoutput shaft 19, rotates at a speed determined from the speed of theplanet carrier assembly member 36, the speed of the sun gear member 32,and the ring gear/sun gear tooth ratio of the planetary gear set 30. Thesun gear member 42 rotates at the same speed as the input shaft 17. Theplanet carrier assembly member 46 rotates at a speed determined from thespeed of the ring gear member 44, the speed of the sun gear member 42,and the ring gear/sun gear tooth ratio of the planetary gear set 40. Thenumerical value of the third forward speed ratio is determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 20, 30and 40.

[0071] The fourth forward speed ratio is established with the engagementof the clutches 52 and 54. The clutch 52 connects the ring gear member24 to the sun gear member 42. The clutch 54 connects the planet carrierassembly member 36 to the planet carrier assembly member 46. The sungear member 22 does not rotate. The ring gear member 24 and sun gearmember 42 rotate at the same speed as the input shaft 17. The planetcarrier assembly member 26 rotates at the same speed as the sun gearmember 32 and the ring gear member 44. The planet carrier assemblymember 26 rotates at a speed determined from the speed of the ring gearmember 24 and the ring gear/sun gear tooth ratio of the planetary gearset 20. The ring gear member 34 rotates at the same speed as the outputshaft 19. The planet carrier assembly member 36 rotates at the samespeed as the planet carrier assembly member 46. The ring gear member 34,and therefore the output shaft 19, rotates at a speed determined fromthe speed of the planet carrier assembly member 36, the speed of the sungear member 32, and the ring gear/sun gear tooth ratio of the planetarygear set 30. The planet carrier assembly member 46 rotates at a speeddetermined from the speed of the ring gear member 44, the speed of thesun gear member 42, and the ring gear/sun gear tooth ratio of theplanetary gear set 40. The numerical value of the fourth forward speedratio is determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 20, 30 and 40.

[0072] The fifth forward speed ratio is established with the engagementof the clutches 54 and 56. In this configuration, the input shaft 17 isdirectly connected to the output shaft 19. The numerical value of thefifth forward speed ratio is 1.

[0073] The sixth forward speed ratio is established with the engagementof the clutches 52 and 56. The clutch 52 connects the ring gear member24 to the sun gear member 42. The clutch 56 connects the planet carrierassembly member 36 to the sun gear member 42. The sun gear member 22does not rotate. The planet carrier assembly member 26 rotates at thesame speed as the sun gear member 32 and the ring gear member 44. Thering gear member 24, sun gear member 42 and planet carrier assemblymember 36 rotate at the same speed as the input shaft 17. The planetcarrier assembly member 26 rotates at a speed determined from the speedof the ring gear member 24 and the ring gear/sun gear tooth ratio of theplanetary gear set 20. The ring gear member 34 rotates at the same speedas the output shaft 19. The ring gear member 34, and therefore theoutput shaft 19, rotates at a speed determined from the speed of theplanet carrier assembly member 36, the speed of the sun gear member 32,and the ring gear/sun gear tooth ratio of the planetary gear set 30. Thenumerical value of the sixth forward speed ratio is determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 20 and30.

[0074] The seventh forward speed ratio is established with theengagement of the clutches 50 and 56. The clutch 50 connects the ringgear member 24 to the planet carrier assembly member 46. The clutch 56connects the planet carrier assembly member 36 to the sun gear member42. The sun gear member 22 does not rotate. The planet carrier assemblymember 26 rotates at the same speed as the sun gear member 32 and thering gear member 44. The ring gear member 24 rotates at the same speedas the planet carrier assembly member 46. The planet carrier assemblymember 26 rotates at a speed determined from the speed of the ring gearmember 24 and the ring gear/sun gear tooth ratio of the planetary gearset 20. The ring gear member 34 rotates at the same speed as the outputshaft 19. The planet carrier assembly member 36 and sun gear member 42rotate at the same speed as the input shaft 17. The ring gear member 34,and therefore the output shaft 19, rotates at a speed determined fromthe speed of the planet carrier assembly member 36, the speed of the sungear member 32, and the ring gear/sun gear tooth ratio of the planetarygear set 30. The planet carrier assembly member 46 rotates at a speeddetermined from the speed of the ring gear member 44, the speed of thesun gear member 42, and the ring gear/sun gear tooth ratio of theplanetary gear set 40. The numerical value of the seventh forward speedratio is determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 20, 30 and 40.

[0075] The eighth forward speed ratio is established with the engagementof the clutch 56 and the brake 58. The clutch 56 connects the planetcarrier assembly member 36 to the sun gear member 42. The brake 58connects the planet carrier assembly member 26 to the transmissionhousing 60. The planetary gear set 20, sun gear member 32, and ring gearmember 44 do not rotate. The planet carrier assembly member 36 and sungear member 42 rotate at the same speed as the input shaft 17. The ringgear member 34 rotates at the same speed as the output shaft 19. Thering gear member 34, and therefore the output shaft 19, rotates at aspeed determined from the speed of the planet carrier assembly member 36and the ring gear/sun gear tooth ratio of the planetary gear set 30. Thenumerical value of the eighth forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratio of the planetary gear set30.

[0076] As set forth above, the engagement schedule for thetorque-transmitting mechanisms is shown in the truth table of FIG. 1b.This truth table also provides an example of speed ratios that areavailable utilizing the ring gear/sun gear tooth ratios given by way ofexample in FIG. 1b. The R1/S1 value is the tooth ratio of the planetarygear set 20; the R2/S2 value is the tooth ratio of the planetary gearset 30; and the R3/S3 value is the tooth ratio of the planetary gear set40. Also, the chart of FIG. 1b describes the ratio steps that areattained utilizing the sample of tooth ratios given. For example, thestep ratio between the first and second forward speed ratios is 2.08,while the step ratio between the reverse and first forward ratio is−0.55. It can also be readily determined from the truth table of FIG. 1bthat all of the single step forward ratio interchanges are of the singletransition variety, as are the double step forward ratio interchanges.

[0077]FIG. 2a shows a powertrain 110 having a conventional engine andtorque converter 12, a planetary transmission 114, and a conventionalfinal drive mechanism 16.

[0078] The planetary transmission 114 includes an input shaft 17continuously connected with the engine and torque converter 12, aplanetary gear arrangement 118, and an output shaft 19 continuouslyconnected with the final drive mechanism 16. The planetary geararrangement 118 includes three planetary gear sets 120, 130 and 140.

[0079] The planetary gear set 120 includes a sun gear member 122, a ringgear member 124, and a planet carrier assembly 126. The planet carrierassembly 126 includes a plurality of pinion gears 127 rotatably mountedon a carrier member 129 and disposed in meshing relationship with boththe sun gear member 122 and the ring gear member 124.

[0080] The planetary gear set 130 includes a sun gear member 132, a ringgear member 134, and a planet carrier assembly member 136. The planetcarrier assembly member 136 includes a plurality of pinion gears 137rotatably mounted on a carrier member 139 and disposed in meshingrelationship with both the sun gear member 132 and the ring gear member134.

[0081] The planetary gear set 140 includes a sun gear member 142, a ringgear member 144, and a planet carrier assembly member 146. The planetcarrier assembly member 146 includes a plurality of pinion gears 147rotatably mounted on a carrier member 149 and disposed in meshingrelationship with both the sun gear member 142 and the ring gear member144.

[0082] The planetary gear arrangement 118 also includes sixtorque-transmitting mechanisms 150, 152, 154, 156, 158 and 159. Thetorque-transmitting mechanisms 150, 152 and 154 are rotating-typetorque-transmitting mechanisms, commonly termed clutches. Thetorque-transmitting mechanisms 156, 158 and 159 are stationary-typetorque-transmitting mechanisms, commonly termed brakes or reactionclutches.

[0083] The input shaft 17 is continuously connected with the sun gearmember 132. The output shaft 19 is continuously connected with the ringgear member 144. The sun gear member 122 is continuously connected withthe transmission housing 160. The planet carrier assembly member 126 iscontinuously connected with the ring gear member 134 and the sun gearmember 142 through the interconnecting member 170.

[0084] The ring gear member 124 is selectively connectable with theplanet carrier assembly member 136 through the clutch 150. The sun gearmember 132 is selectively connectable with the planet carrier assemblymember 146 through the clutch 152. The planet carrier assembly member136 is selectively connectable with the planet carrier assembly member146 through the clutch 154. The ring gear member 124 is selectivelyconnectable with the transmission housing 160 through the brake 156. Theplanet carrier assembly member 136 is selectively connectable with thetransmission housing 160 through the brake 158. The planet carrierassembly member 146 is selectively connectable with the transmissionhousing 160 through the brake 159.

[0085] The truth table of FIG. 2b describes the engagement sequenceutilized to provide seven forward speed ratios and a reverse speed ratioin the planetary gear arrangement 118 shown in FIG. 2a.

[0086] The reverse speed ratio is established with the engagement of theclutch 150 and the brake 159. The clutch 150 connects the ring gearmember 124 to the planet carrier assembly member 136. The brake 159connects the planet carrier assembly member 146 to the transmissionhousing 160. The ring gear member 124 rotates at the same speed as theplanet carrier assembly member 136. The planet carrier assembly member126 rotates at the same speed as the ring gear member 134 and the sungear member 142. The sun gear member 122 does not rotate. The planetcarrier assembly member 126 rotates at a speed determined from the speedof the ring gear member 124 and the ring gear/sun gear tooth ratio ofthe planetary gear set 120. The sun gear member 132 rotates at the samespeed as the input shaft 17. The planet carrier assembly member 136rotates at a speed determined from the speed of the ring gear member134, the speed of the sun gear member 132, and the ring gear/sun geartooth ratio of the planetary gear set 130. The planet carrier assemblymember 146 does not rotate. The ring gear member 144 rotates at the samespeed as the output shaft 19. The ring gear member 144, and thereforethe output shaft 19, rotates at a speed determined from the speed of thesun gear member 142 and the ring gear/sun gear tooth ratio of theplanetary gear set 140. The numerical value of the reverse speed ratiois determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 120, 130 and 140.

[0087] The first forward speed ratio is established with the engagementof the clutch 154 and the brake 159. The clutch 154 connects the planetcarrier assembly member 136 to the planet carrier assembly member 146.The brake 159 connects the planet carrier assembly member 146 to thetransmission housing 160. The planet carrier assembly member 126 rotatesat the same speed as the ring gear member 134 and the sun gear member142. The sun gear member 122 does not rotate. The sun gear member 132rotates at the same speed as the input shaft 17. The planet carrierassembly members 136 and 146 do not rotate. The ring gear member 134rotates at a speed determined from the speed of the sun gear member 132and the ring gear/sun gear tooth ratio of the planetary gear set 130.The ring gear member 144 rotates at the same speed as the output shaft19. The ring gear member 144, and therefore the output shaft 19, rotatesat a speed determined from the speed of the sun gear member 142 and thering gear/sun gear tooth ratio of the planetary gear set 140. Thenumerical value of the first forward speed ratio is determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 130 and140.

[0088] The second forward speed ratio is established with the engagementof the clutch 154 and the brake 156. The clutch 154 connects the planetcarrier assembly member 136 to the planet carrier assembly member 146.The brake 156 connects the ring gear member 124 to the transmissionhousing 160. The planetary gear set 120, ring gear member 134, and sungear member 142 do not rotate. The planet carrier assembly member 136rotates at the same speed as the planet carrier assembly member 146. Thesun gear member 132 rotates at the same speed as the input shaft 17. Theplanet carrier assembly member 136 rotates at a speed determined fromthe speed of the sun gear member 132 and the ring gear/sun gear toothratio of the planetary gear set 130. The ring gear member 144 rotates atthe same speed as the output shaft 19. The ring gear member 144, andtherefore the output shaft 19, rotates at a speed determined from thespeed of the planet carrier assembly member 146 and the ring gear/sungear tooth ratio of the planetary gear set 140. The numerical value ofthe second forward speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 130 and 140.

[0089] The third forward speed ratio is established with the engagementof the clutches 150 and 154. The clutch 150 connects the ring gearmember 124 to the planet carrier assembly member 136. The clutch 154connects the planet carrier assembly member 136 to the planet carrierassembly member 146. The ring gear member 124 rotates at the same speedas the planet carrier assembly members 136 and 146. The planet carrierassembly member 126 rotates at the same speed as the ring gear member134 and the sun gear member 142. The sun gear member 122 does notrotate. The planet carrier assembly member 126 rotates at a speeddetermined from the speed of the ring gear member 124 and the ringgear/sun gear tooth ratio of the planetary gear set 120. The sun gearmember 132 rotates at the same speed as the input shaft 17. The planetcarrier assembly member 136 rotates at a speed determined from the speedof the ring gear member 134, the speed of the sun gear member 132, andthe ring gear/sun gear tooth ratio of the planetary gear set 130. Thering gear member 144 rotates at the same speed as the output shaft 19.The ring gear member 144, and therefore the output shaft 19, rotates ata speed determined from the speed of the planet carrier assembly member146, the speed of the sun gear member 142 and the ring gear/sun geartooth ratio of the planetary gear set 140. The numerical value of thethird forward speed ratio is determined utilizing the ring gear/sun geartooth ratios of the planetary gear sets 120, 130 and 140.

[0090] The fourth forward speed ratio is established with the engagementof the clutches 152 and 154. In this configuration, the input shaft 17is directly connected to the output shaft 19. The numerical value of thefourth forward speed ratio is 1.

[0091] The fifth forward speed ratio is established with the engagementof the clutches 150 and 152. The clutch 150 connects the ring gearmember 124 to the planet carrier assembly member 136. The clutch 152connects the sun gear member 132 to the planet carrier assembly member146. The ring gear member 124 rotates at the same speed as the planetcarrier assembly member 136. The planet carrier assembly member 126rotates at the same speed as the ring gear member 134 and the sun gearmember 142. The sun gear member 122 does not rotate. The planet carrierassembly member 126 rotates at a speed determined from the speed of thering gear member 124 and the ring gear/sun gear tooth ratio of theplanetary gear set 120. The sun gear member 132 and planet carrierassembly member 146 rotate at the same speed as the input shaft 17. Theplanet carrier assembly member 136 rotates at a speed determined fromthe speed of the ring gear member 134, the speed of the sun gear member132, and the ring gear/sun gear tooth ratio of the planetary gear set130. The ring gear member 144 rotates at the same speed as the outputshaft 19. The ring gear member 144, and therefore the output shaft 19,rotates at a speed determined from the speed of the planet carrierassembly member 146, the speed of the sun gear member 142 and the ringgear/sun gear tooth ratio of the planetary gear set 140. The numericalvalue of the fifth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 120, 130 and 140.

[0092] The sixth forward speed ratio is established with the engagementof the clutch 152 and the brake 156. The clutch 152 connects the sungear member 132 to the planet carrier assembly member 146. The brake 156connects the ring gear member 124 to the transmission housing 160. Theplanetary gear set 120, ring gear member 134, and sun gear member 142 donot rotate. The sun gear member 132 and planet carrier assembly member146 rotate at the same speed as the input shaft 17. The ring gear member144 rotates at the same speed as the output shaft 19. The ring gearmember 144, and therefore the output shaft 19, rotates at a speeddetermined from the speed of the planet carrier assembly member 146 andthe ring gear/sun gear tooth ratio of the planetary gear set 140. Thenumerical value of the sixth forward speed ratio is determined utilizingthe ring gear/sun gear tooth ratio of the planetary gear set 140.

[0093] The seventh forward speed ratio is established with theengagement of the clutch 152 and the brake 158. The clutch 152 connectsthe sun gear member 132 to the planet carrier assembly member 146. Thebrake 158 connects the planet carrier assembly member 136 to thetransmission housing 160. The planet carrier assembly member 126 rotatesat the same speed as the ring gear member 134 and the sun gear member142. The sun gear member 122 and planet carrier assembly member 136 donot rotate. The sun gear member 132 and planet carrier assembly member146 rotate at the same speed as the input shaft 17. The ring gear member134 rotates at a speed determined from the speed of the sun gear member132 and the ring gear/sun gear tooth ratio of the planetary gear set130. The ring gear member 144 rotates at the same speed as the outputshaft 19. The ring gear member 144, and therefore the output shaft 19,rotates at a speed determined from the speed of the planet carrierassembly member 146, the speed of the sun gear member 142, and the ringgear/sun gear tooth ratio of the planetary gear set 140. The numericalvalue of the seventh forward speed ratio is determined utilizing thering gear/sun gear tooth ratios of the planetary gear sets 130 and 140.

[0094] As set forth above, the truth table of FIG. 2b describes theengagement sequence of the torque-transmitting mechanisms utilized toprovide a reverse drive ratio and seven forward speed ratios. The truthtable also provides an example of the ratios that can be attained withthe family members shown in FIG. 2a utilizing the sample tooth ratiosgiven in FIG. 2b. The R1/S1 value is the tooth ratio of the planetarygear set 120; the R2/S2 value is the tooth ratio of the planetary gearset 130; and the R3/S3 value is the tooth ratio of the planetary gearset 140. Also shown in FIG. 2b are the ratio steps between single stepratios in the forward direction as well as the reverse to first ratiostep ratio. For example, the first to second step ratio is 1.96.

[0095] Turning to FIG. 3a, a powertrain 210 includes the engine andtorque converter 12, a planetary transmission 214, and a final drivemechanism 16. The planetary transmission 214 includes an input shaft 17continuously connected with the engine and torque converter 12, aplanetary gear arrangement 218, and an output shaft 19 continuouslyconnected with the final drive mechanism 16. The planetary geararrangement 218 includes three planetary gear sets 220, 230 and 240.

[0096] The planetary gear set 220 includes a sun gear member 222, a ringgear member 224, and a planet carrier assembly 226. The planet carrierassembly 226 includes a plurality of pinion gears 227 rotatably mountedon a carrier member 229 and disposed in meshing relationship with boththe sun gear member 222 and the ring gear member 224.

[0097] The planetary gear set 230 includes a sun gear member 232, a ringgear member 234, and a planet carrier assembly member 236. The planetcarrier assembly member 236 includes a plurality of pinion gears 237rotatably mounted on a carrier member 239 and disposed in meshingrelationship with both the sun gear member 232 and the ring gear member234.

[0098] The planetary gear set 240 includes a sun gear member 242, a ringgear member 244, and a planet carrier assembly member 246. The planetcarrier assembly member 246 includes a plurality of pinion gears 247rotatably mounted on a carrier member 249 and disposed in meshingrelationship with both the sun gear member 242 and the ring gear member244.

[0099] The planetary gear arrangement 218 also includes sixtorque-transmitting mechanisms 250, 252, 254, 256, 258 and 259. Thetorque-transmitting mechanisms 250, 252, 254 and 256 are rotating typetorque-transmitting mechanisms, commonly termed clutches. Thetorque-transmitting mechanisms 258 and 259 are stationary typetorque-transmitting mechanisms, commonly termed brakes or reactionclutches.

[0100] The input shaft 17 is continuously connected with the sun gearmember 242, and the output shaft 19 is continuously connected with thering gear member 234. The sun gear member 222 is continuously connectedwith the transmission housing 260. The ring gear member 224 iscontinuously connected with the sun gear member 232 and the planetcarrier assembly member 246 through the interconnecting member 270.

[0101] The planet carrier assembly member 226 is selectively connectablewith the planet carrier assembly member 236 through the clutch 250. Theplanet carrier assembly member 226 is selectively connectable with thering gear member 244 through the clutch 152. The planet carrier assemblymember 246 is selectively connectable with the sun gear member 242through the clutch 254. The planet carrier assembly member 236 isselectively connectable with the sun gear member 242 through the clutch256. The planet carrier assembly member 236 is selectively connectablewith the transmission housing 260 through the brake 258. The ring gearmember 244 is selectively connectable with the transmission housing 260through the brake 259.

[0102] As shown in the truth table in FIG. 3b, the torque-transmittingmechanisms are engaged in combinations of two to establish seven forwardspeed ratios and one reverse ratio.

[0103] The reverse speed ratio is established with the engagement of theclutch 254 and the brake 258. The clutch 254 connects the planet carrierassembly member 246 to the sun gear member 242. The brake 258 connectsthe planet carrier assembly member 236 to the transmission housing 260.The sun gear member 222 does not rotate. The ring gear member 224, sungear member 232, planet carrier assembly member 246, and sun gear member242 rotate at the same speed as the input shaft 17. The planet carrierassembly member 236 does not rotate. The ring gear member 234 rotates atthe same speed as the output shaft 19. The ring gear member 234, andtherefore the output shaft 19, rotates at a speed determined from thespeed of the sun gear member 232 and the ring gear/sun gear tooth ratioof the planetary gear set 230. The numerical value of the reverse speedratio is determined utilizing the ring gear/sun gear tooth ratio of theplanetary gear set 230.

[0104] The first forward speed ratio is established with the engagementof the clutch 250 and the brake 259. The clutch 250 connects the planetcarrier assembly member 226 to the planet carrier assembly member 236.The brake 259 connects the ring gear member 244 to the transmissionhousing 260. The sun gear member 222 does not rotate. The planet carrierassembly member 226 rotates at the same speed as the planet carrierassembly member 236. The ring gear member 224 rotates at the same speedas the sun gear member 232 and the planet carrier assembly member 246.The planet carrier assembly member 226 rotates at a speed determinedfrom the speed of the ring gear member 224 and the ring gear/sun geartooth ratio of the planetary gear set 220. The ring gear member 234rotates at the same speed as the output shaft 19. The ring gear member234, and therefore the output shaft 19, rotates at a speed determinedfrom the speed of the planet carrier assembly member 236, the speed ofthe sun gear member 232, and the ring gear/sun gear tooth ratio of theplanetary gear set 230. The sun gear member 242 rotates at the samespeed as the input shaft 17. The ring gear member 244 does not rotate.The planet carrier assembly member 246 rotates at a speed determinedfrom the speed of the sun gear member 242 and the ring gear/sun geartooth ratio of the planetary gear set 240. The numerical value of thefirst forward speed ratio is determined utilizing the ring gear/sun geartooth ratios of the planetary gear sets 220, 230 and 240.

[0105] The second forward speed ratio is established with the engagementof the clutches 250 and 252. The clutch 250 connects the planet carrierassembly member 226 to the planet carrier assembly member 236. Theclutch 252 connects the planet carrier assembly member 226 to the ringgear member 244. The ring gear member 224 rotates at the same speed asthe sun gear member 232 and the planet carrier assembly member 246. Theplanet carrier assembly member 226 rotates at the same speed as theplanet carrier assembly member 236 and the ring gear member 244. The sungear member 222 does not rotate. The planet carrier assembly member 226rotates at a speed determined from the speed of the ring gear member 224and the ring gear/sun gear tooth ratio of the planetary gear set 220.The ring gear member 234 rotates at the same speed as the output shaft19. The ring gear member 234, and therefore the output shaft 19, rotatesat a speed determined from the speed of the planet carrier assemblymember 236, the speed of the sun gear member 232, and the ring gear/sungear tooth ratio of the planetary gear set 230. The sun gear member 242rotates at the same speed as the input shaft 17. The planet carrierassembly member 246 rotates at a speed determined from the speed of thering gear member 244, the speed of the sun gear member 242, and the ringgear/sun gear tooth ratio of the planetary gear set 240. The numericalvalue of the second forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 220, 230 and 240.

[0106] The third forward speed ratio is established with the engagementof the clutches 250 and 254. The clutch 250 connects the planet carrierassembly member 226 to the planet carrier assembly member 236. Theclutch 254 connects the planet carrier assembly member 246 to the sungear member 242. The sun gear member 222 does not rotate. The planetcarrier assembly member 226 rotates at the same speed as the planetcarrier assembly member 236. The ring gear member 224, sun gear member232, planet carrier assembly member 246, and sun gear member 242 rotateat the same speed as the input shaft 17. The planet carrier assemblymember 226 rotates at a speed determined from the speed of the ring gearmember 224 and the ring gear/sun gear tooth ratio of the planetary gearset 220. The ring gear member 234 rotates at the same speed as theoutput shaft 19. The ring gear member 234, and therefore the outputshaft 19, rotates at a speed determined from the speed of the planetcarrier assembly member 236, the speed of the sun gear member 232, andthe ring gear/sun gear tooth ratio of the planetary gear set 230. Thenumerical value of the third forward speed ratio is determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 220 and230.

[0107] The fourth forward speed ratio is established with the engagementof the clutches 250 and 256. The clutch 250 connects the planet carrierassembly member 226 to the planet carrier assembly member 236. Theclutch 256 connects the planet carrier assembly member 236 to the sungear member 242. The sun gear member 222 does not rotate. The planetcarrier assembly member 226, planet carrier assembly member 236, and sungear member 242 rotate at the same speed as the input shaft 17. The ringgear member 224 rotates at the same speed as the sun gear member 232 andthe planet carrier assembly member 246. The planet carrier assemblymember 226 rotates at a speed determined from the speed of the ring gearmember 224 and the ring gear/sun gear tooth ratio of the planetary gearset 220. The ring gear member 234 rotates at the same speed as theoutput shaft 19. The ring gear member 234, and therefore the outputshaft 19, rotates at a speed determined from the speed of the planetcarrier assembly member 236, the speed of the sun gear member 232, andthe ring gear/sun gear tooth ratio of the planetary gear set 230. Thenumerical value of the fourth forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets220 and 230.

[0108] The fifth forward speed ratio is established with the engagementof the clutches 254 and 256. In this configuration, the input shaft 17is directly connected to the output shaft 19. The numerical value of thefifth forward speed ratio is 1.

[0109] The sixth forward speed ratio is established with the engagementof the clutches 252 and 256. The clutch 252 connects the planet carrierassembly member 226 to the ring gear member 244. The clutch 256 connectsthe planet carrier assembly member 236 to the sun gear member 242. Thesun gear member 222 does not rotate. The planet carrier assembly member226 rotates at the same speed as the ring gear member 244. The ring gearmember 224 rotates at the same speed as the sun gear member 232 and theplanet carrier assembly member 246. The planet carrier assembly member226 rotates at a speed determined from the speed of the ring gear member224 and the ring gear/sun gear tooth ratio of the planetary gear set220. The ring gear member 234 rotates at the same speed as the outputshaft 19. The planet carrier assembly member 236 and sun gear member 242rotate at the same speed as the input shaft 17. The ring gear member234, and therefore the output shaft 19, rotates at a speed determinedfrom the speed of the planet carrier assembly member 236, the speed ofthe sun gear member 242, and the ring gear/sun gear tooth ratio of theplanetary gear set 230. The planet carrier assembly member 246 rotatesat a speed determined from the speed of the ring gear member 244, thespeed of the sun gear member 242, and the ring gear/sun gear tooth ratioof the planetary gear set 240. The numerical value of the sixth forwardspeed ratio is determined utilizing the ring gear/sun gear tooth ratiosof the planetary gear sets 220, 230 and 240.

[0110] The seventh forward speed ratio is established with theengagement of the clutch 256 and the brake 259. The clutch 256 connectsthe planet carrier assembly member 236 to the sun gear member 242. Thebrake 259 connects the ring gear member 244 to the transmission housing260. The sun gear member 222 does not rotate. The ring gear member 224rotates at the same speed as the sun gear member 232 and the planetcarrier assembly member 246. The planet carrier assembly member 236 andsun gear member 242 rotate at the same speed as the input shaft 17. Thering gear member 234 rotates at the same speed as the output shaft 19.The ring gear member 234, and therefore the output shaft 19, rotates ata speed determined from the speed of the planet carrier assembly member236, the speed of the sun gear member 232, and the ring gear/sun geartooth ratio of the planetary gear set 230. The ring gear member 244 doesnot rotate. The planet carrier assembly member 246 rotates at a speeddetermined from the speed of the sun gear member 242 and the ringgear/sun gear tooth ratio of the planetary gear set 240. The numericalvalue of the seventh forward speed ratio is determined utilizing thering gear/sun gear tooth ratios of the planetary gear sets 230 and 240.

[0111] As previously set forth, the truth table of FIG. 3b describes thecombinations of engagements utilized for the seven forward speed ratiosand reverse ratio. The truth table also provides an example of speedratios that are available with the family member described above. Theseexamples of speed ratios are determined utilizing the tooth ratios givenin FIG. 3b. The R1/S1 value is the tooth ratio of the planetary gear set220; the R2/S2 value is the tooth ratio of the planetary gear set 230;and the R3/S3 value is the tooth ratio of the planetary gear set 240.Also depicted in FIG. 3b is a chart representing the ratio steps betweenadjacent forward speed ratios and the reverse speed ratio. For example,the first to second ratio interchange has a step of 1.66. It can also bereadily determined from the truth table of FIG. 3b that all of thesingle step forward ratio interchanges are of the single transitionvariety, except the reverse to first step. The double step forward ratiointerchanges are also of the single transition variety.

[0112] A powertrain 310, shown in FIG. 4a, includes the engine andtorque converter 12, a planetary transmission 314, and the final drivemechanism 16. The planetary transmission 314 includes an input shaft 17continuously connected with the engine and torque converter 12, aplanetary gear arrangement 318, and output shaft 19 continuouslyconnected with the final drive mechanism 16. The planetary geararrangement 318 includes three planetary gear sets 320, 330 and 340.

[0113] The planetary gear set 320 includes a sun gear member 322, a ringgear member 324, and a planet carrier assembly member 326. The planetcarrier assembly member 326 includes a plurality of pinion gears 327rotatably mounted on a carrier member 329 and disposed in meshingrelationship with both the sun gear member 322 and the ring gear member324.

[0114] The planetary gear set 330 includes a sun gear member 332, a ringgear member 334, and a planet carrier assembly member 336. The planetcarrier assembly member 336 includes a plurality of pinion gears 337rotatably mounted on a carrier member 339 and disposed in meshingrelationship with both the sun gear member 332 and the ring gear member334.

[0115] The planetary gear set 340 includes a sun gear member 342, a ringgear member 344, and a planet carrier assembly member 346. The planetcarrier assembly member 346 includes a plurality of pinion gears 347rotatably mounted on a carrier member 349 and disposed in meshingrelationship with both the sun gear member 342 and the ring gear member344.

[0116] The planetary gear arrangement 318 also includes sixtorque-transmitting mechanisms 350, 352, 354, 356, 358 and 359. Thetorque-transmitting mechanisms 350, 352, 354 and 356 are rotating typetorque-transmitting mechanisms, commonly termed clutches. Thetorque-transmitting mechanisms 358 and 359 are stationary-typetorque-transmitting mechanisms, commonly termed brakes or reactionclutches.

[0117] The input shaft 17 is continuously connected with the sun gearmember 332, and the output shaft 19 is continuously connected with thering gear member 344. The sun gear member 322 is continuously connectedwith the transmission housing 360. The planet carrier assembly member326 is continuously connected with the ring gear member 334 and the sungear member 342 through the interconnecting member 370.

[0118] The ring gear member 324 is selectively connectable with the sungear member 332 through the clutch 350. The ring gear member 324 isselectively connectable with the planet carrier assembly member 336through the clutch 352. The sun gear member 332 is selectivelyconnectable with the planet carrier assembly member 346 through theclutch 354. The planet carrier assembly member 336 is selectivelyconnectable with the planet carrier assembly member 346 through theclutch 356. The ring gear member 324 is selectively connectable with thetransmission housing 360 through the brake 358. The planet carrierassembly member 346 is selectively connectable with the transmissionhousing 360 through the brake 359.

[0119] The truth tables given in FIGS. 4b, 5 b, 6 b, 7 b, 8 b, 9 b, 10b, 11 b, 12 b, 13 b, 14 b, 15 b, 16 b, 17 b and 18 b show the engagementsequences for the torque-transmitting mechanisms to provide at leastseven forward speed ratios and at least one reverse ratio. As shown anddescribed above for the configuration in FIGS. 1a, 2 a and 3 a, thoseskilled in the art will understand from the respective truth tables howthe speed ratios are established through the planetary gear setsidentified in the written description.

[0120] The truth table shown in FIG. 4b describes the engagementcombination and the engagement sequence necessary to provide the reversedrive ratio and seven forward speed ratios. A sample of the numericalvalues for the ratios is also provided in the truth table of FIG. 4b.These values are determined utilizing the ring gear/sun gear toothratios also given in FIG. 4b. The R1/S1 value is the tooth ratio for theplanetary gear set 320; the R2/S2 value is the tooth ratio for theplanetary gear set 330; and the R3/S3 value is the tooth ratio for theplanetary gear set 340. Also given in FIG. 4b is a chart describing thestep ratios between the adjacent forward speed ratios and the reverse tofirst forward speed ratio. For example, the first to second forwardspeed ratio step is 2.1. It can be readily determined from the truthtable of FIG. 4b that each of the forward single step ratio interchangesis a single transition shift, as are the double step interchanges.

[0121] Those skilled in the art will recognize that the numerical valuesof the reverse and sixth forward speed ratios are determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 320 and340. The numerical values of the first and second forward speed ratiosare determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 330 and 340. The numerical values of the third,fourth and seventh forward speed ratios are determined utilizing thering gear/sun gear tooth ratios of the planetary gear sets 320, 330 and340. The numerical value of the fifth forward speed ratio is 1.

[0122] A powertrain 410, shown in FIG. 5a, includes the engine andtorque converter 12, a planetary transmission 414 and the final drivemechanism 16. The planetary transmission 414 includes a planetary geararrangement 418, input shaft 17 and output shaft 19. The planetary geararrangement 418 includes three simple planetary gear sets 420, 430 and440.

[0123] The planetary gear set 420 includes a sun gear member 422, a ringgear member 424, and a planet carrier assembly 426. The planet carrierassembly 426 includes a plurality of pinion gears 427 rotatably mountedon a carrier member 429 and disposed in meshing relationship with boththe sun gear member 422 and the ring gear member 424.

[0124] The planetary gear set 430 includes a sun gear member 432, a ringgear member 434, and a planet carrier assembly member 436. The planetcarrier assembly member 436 includes a plurality of pinion gears 437rotatably mounted on a carrier member 439 and disposed in meshingrelationship with both the sun gear member 432 and the ring gear member434.

[0125] The planetary gear set 440 includes a sun gear member 442, a ringgear member 444, and a planet carrier assembly member 446. The planetcarrier assembly member 446 includes a plurality of pinion gears 447rotatably mounted on a carrier member 449 and disposed in meshingrelationship with both the sun gear member 442 and the ring gear member444.

[0126] The planetary gear arrangement 418 also includes sixtorque-transmitting mechanisms 450, 452, 454, 456, 458 and 459. Thetorque-transmitting mechanisms 450, 452, 454 and 456 are rotating typetorque-transmitting mechanisms, commonly termed clutches. Thetorque-transmitting mechanisms 458 and 459 are stationary-typetorque-transmitting mechanisms, commonly termed brakes or reactionclutches.

[0127] The input shaft 17 is continuously connected with the sun gearmember 442, and the output shaft 19 is continuously connected with thering gear member 434. The sun gear member 422 is continuously connectedwith the transmission housing 460. The planet carrier assembly member426 is continuously connected with the sun gear member 432 and the ringgear member 444 through the interconnecting member 470.

[0128] The ring gear member 424 is selectively connectable with theplanet carrier assembly member 426 through the clutch 450. The ring gearmember 424 is selectively connectable with the planet carrier assemblymember 446 through the clutch 452. The planet carrier assembly member436 is selectively connectable with the planet carrier assembly member446 through the clutch 454. The planet carrier assembly member 436 isselectively connectable with the sun gear member 442 through the clutch456. The planet carrier assembly member 436 is selectively connectablewith the transmission housing 460 through the brake 458. The planetcarrier assembly member 446 is selectively connectable with thetransmission housing 460 through the brake 459.

[0129] The truth table shown in FIG. 5b describes the engagementcombination and sequence of the torque-transmitting mechanisms 450, 452,454, 456, 458 and 459 that are employed to provide the reverse driveratio and the seven forward speed ratios. It should be noted that thetorque-transmitting mechanism 458 is engaged through the neutralcondition to simplify the forward/reverse interchange.

[0130] Also given in the truth table of FIG. 5b is a set of numericalvalues that are attainable with the present invention utilizing the ringgear/sun gear tooth ratios shown. The R1/S1 value is the tooth ratio ofthe planetary gear set 420; the R2/S2 value is the tooth ratio of theplanetary gear set 430; and the R3/S3 value is the tooth ratio of theplanetary gear set 440. As can also be determined from the truth tableof FIG. 5b, the single and double step forward interchanges are singletransition shifts.

[0131]FIG. 5b also provides a chart of the ratio steps between adjacentforward ratios and between the reverse and first forward ratio. Forexample, the ratio step between the first and second forward ratios is1.81. Those skilled in the art will recognize that the numerical valuesof the reverse, third and fifth forward speed ratios are determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets420, 430 and 440. The numerical values of the first, second and seventhforward speed ratios are determined utilizing the ring gear/sun geartooth ratios of the planetary gear sets 430 and 440. The numerical valueof the fourth forward speed ratio is 1. The numerical value of the sixthforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 430.

[0132] A powertrain 510, shown in FIG. 6a, includes an engine and torqueconverter 12, a planetary gear transmission 514 and the final drivemechanism 16. The planetary transmission 514 includes the input shaft17, a planetary gear arrangement 518 and the output shaft 19. Theplanetary gear arrangement 518 includes three planetary gear sets 520,530 and 540.

[0133] The planetary gear set 520 includes a sun gear member 522, a ringgear member 524, and a planet carrier assembly 526. The planet carrierassembly 526 includes a plurality of pinion gears 527 rotatably mountedon a carrier member 529 and disposed in meshing relationship with boththe sun gear member 522 and the ring gear member 524.

[0134] The planetary gear set 530 includes a sun gear member 532, a ringgear member 534, and a planet carrier assembly member 536. The planetcarrier assembly member 536 includes a plurality of pinion gears 537rotatably mounted on a carrier member 539 and disposed in meshingrelationship with both the sun gear member 532 and the ring gear member534.

[0135] The planetary gear set 540 includes a sun gear member 542, a ringgear member 544, and a planet carrier assembly member 546. The planetcarrier assembly member 546 includes a plurality of pinion gears 547rotatably mounted on a carrier member 549 and disposed in meshingrelationship with both the sun gear member 542 and the ring gear member544.

[0136] The planetary gear arrangement 518 also includes sixtorque-transmitting mechanisms 550, 552, 554, 556, 558 and 559. Thetorque-transmitting mechanisms 550, 552, 554 and 556 are rotating typetorque-transmitting mechanisms, commonly termed clutches. Thetorque-transmitting mechanisms 558 and 559 are stationary-typetorque-transmitting mechanisms, commonly termed brakes or reactionclutches.

[0137] The input shaft 17 is continuously connected with the sun gearmember 542, and the output shaft 19 is continuously connected with thering gear member 534. The planet carrier assembly member 526 iscontinuously connected with the transmission housing 560. The sun gearmember 522 is continuously connected with the sun gear member 532 andwith the ring gear member 544 through the interconnecting member 570.

[0138] The ring gear member 524 is selectively connectable with theplanet carrier assembly member 546 through the clutch 550. The planetcarrier assembly member 536 is selectively connectable with the sun gearmember 532 through the clutch 552. The planet carrier assembly member536 is selectively connectable with the planet carrier assembly member546 through the clutch 554. The planet carrier assembly member 536 isselectively connectable with the sun gear member 542 through the clutch556. The sun gear member 522 is selectively connectable with thetransmission housing 560 through the brake 558. The planet carrierassembly member 546 is selectively connectable with the transmissionhousing 560 through the brake 559.

[0139] The truth table shown in FIG. 6b describes the engagementsequence and combination of the torque-transmitting mechanisms toprovide two reverse speed ratios and seven forward speed ratios. Itshould be noted that the torque-transmitting mechanism 559 can remainengaged through the neutral condition, thereby simplifying theforward/reverse interchange. It can also be determined from the truthtable of FIG. 6b that all of the single and double step forward ratiointerchanges are of the single transition variety. The chart of FIG. 6bdescribes the ratio steps between adjacent forward speed ratios and theratio step between the reverse and first forward speed ratio.

[0140] Those skilled in the art, upon reviewing the truth table and theschematic representation of FIG. 6a, can determine that the numericalvalue of the reverse speed ratio is determined utilizing the ringgear/sun gear tooth ratio of the planetary gear set 540. The numericalvalues of the first, third and seventh forward speed ratios aredetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 530 and 540. The numerical values of the second andsixth forward speed ratios are determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 520, 530 and 540. Thenumerical value of the fourth forward speed ratio is 1. The numericalvalue of the fifth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratio of the planetary gear set 530.

[0141] The sample speed ratios given in the truth table are determinedutilizing the tooth ratio values also given in FIG. 6b. The R1/S1 valueis the tooth ratio of the planetary gear set 520; the R2/S2 value is thetooth ratio of the planetary gear set 530; and the R3/S3 value is thetooth ratio of the planetary gear set 540.

[0142] A powertrain 610, shown in FIG. 7a, has the engine and torqueconverter 12, a planetary transmission 614 and the final drive mechanism16. The planetary transmission 614 includes the input shaft 17, aplanetary gear arrangement 618 and the output shaft 19. The planetarygear arrangement 618 includes three planetary gear sets 620, 630 and640.

[0143] The planetary gear set 620 includes a sun gear member 622, a ringgear member 624, and a planet carrier assembly 626. The planet carrierassembly 626 includes a plurality of pinion gears 627 rotatably mountedon a carrier member 629 and disposed in meshing relationship with boththe sun gear member 622 and the ring gear member 624.

[0144] The planetary gear set 630 includes a sun gear member 632, a ringgear member 634, and a planet carrier assembly member 636. The planetcarrier assembly member 636 includes a plurality of pinion gears 637rotatably mounted on a carrier member 639 and disposed in meshingrelationship with both the sun gear member 632 and the ring gear member634.

[0145] The planetary gear set 640 includes a sun gear member 642, a ringgear member 644, and a planet carrier assembly member 646. The planetcarrier assembly member 646 includes a plurality of pinion gears 647rotatably mounted on a carrier member 649 and disposed in meshingrelationship with both the sun gear member 642 and the ring gear member644.

[0146] The planetary gear arrangement 618 also includes sixtorque-transmitting mechanisms 650, 652, 654, 656, 658 and 659. Thetorque-transmitting mechanisms 650, 652, 654, 656 and 658 are rotatingtype torque-transmitting mechanisms, commonly termed clutches. Thetorque-transmitting mechanism 659 is a stationary-typetorque-transmitting mechanism, commonly termed a brake or reactionclutch.

[0147] The input shaft 17 is continuously connected with the planetcarrier assembly member 626, and the output shaft 19 is continuouslyconnected with the planet carrier assembly member 646. The ring gearmember 624 is continuously connected with the transmission housing 660.The planet carrier assembly member 626 is continuously connected withthe sun gear member 632 and ring gear member 644 through theinterconnecting member 670.

[0148] The sun gear member 622 is selectively connectable with theplanet carrier assembly member 636 through the clutch 650. The ring gearmember 634 is selectively connectable with the planet carrier assemblymember 646 through the clutch 652. The ring gear member 634 isselectively connectable with the sun gear member 642 through the clutch654. The planet carrier assembly member 636 is selectively connectablewith the planet carrier assembly member 646 through the clutch 656. Theplanet carrier assembly member 636 is selectively connectable with thesun gear member 642 through the clutch 658. The planet carrier assemblymember 636 is selectively connectable with the transmission housing 660through the brake 659.

[0149] The truth table shown in FIG. 7b describes the combination oftorque-transmitting mechanism engagements that will provide the reversedrive ratio and seven forward speed ratios, as well as the sequence ofthese engagements and interchanges. The torque-transmitting mechanism659 can be engaged through the neutral condition, thereby simplifyingthe forward/reverse interchange. It can be noted from the truth tablethat each of the single step forward interchanges are single transitionratio changes.

[0150] The ratio values given are by way of example and are establishedutilizing the ring gear/sun gear tooth ratios given in FIG. 7b. Forexample, the R1/S1 value is the tooth ratio of the planetary gear set620; the R2/S2 value is the tooth ratio of the planetary gear set 630;and the R3/S3 value is the tooth ratio of the planetary gear set 640.The ratio steps between adjacent forward ratios and the reverse to firstratio are also given in FIG. 7b.

[0151] Those skilled in the art will, upon reviewing the truth table ofFIG. 7b, recognize that the numerical value of the reverse speed ratiois determined utilizing the ring gear/sun gear tooth ratio of theplanetary gear set 630. The numerical value of the first forward speedratio is determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 630 and 640. The numerical value of the secondforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 640. The numerical value of the thirdforward speed ratio is 1. The numerical value of the fourth forwardspeed ratio is determined utilizing the ring gear/sun gear tooth ratiosof the planetary gear sets 620 and 640. The numerical value of the fifthforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 620, 630 and 640. The numerical valueof the sixth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratio of the planetary gear set 620. The numericalvalue of the seventh forward speed ratio is determined utilizing thering gear/sun gear tooth ratios of the planetary gear sets 620 and 630.

[0152] A powertrain 710, shown in FIG. 8a, has the conventional engineand torque converter 12, a planetary transmission 714, and theconventional final drive mechanism 16. The engine and torque converter12 are drivingly connected with the planetary transmission 714 throughthe input shaft 17. The planetary transmission 714 is drivinglyconnected with the final drive mechanism 16 through the output shaft 19.The planetary transmission 714 includes a planetary gear arrangement 718that has a first planetary gear set 720, a second planetary gear set730, and a third planetary gear set 740.

[0153] The planetary gear set 720 includes a sun gear member 722, a ringgear member 724, and a planet carrier assembly 726. The planet carrierassembly 726 includes a plurality of pinion gears 727 rotatably mountedon a carrier member 729 and disposed in meshing relationship with boththe sun gear member 722 and the ring gear member 724.

[0154] The planetary gear set 730 includes a sun gear member 732, a ringgear member 734, and a planet carrier assembly member 736. The planetcarrier assembly member 736 includes a plurality of pinion gears 737rotatably mounted on a carrier member 739 and disposed in meshingrelationship with both the sun gear member 732 and the ring gear member734.

[0155] The planetary gear set 740 includes a sun gear member 742, a ringgear member 744, and a planet carrier assembly member 746. The planetcarrier assembly member 746 includes a plurality of pinion gears 747rotatably mounted on a carrier member 749 and disposed in meshingrelationship with both the sun gear member 742 and the ring gear member744.

[0156] The planetary gear arrangement 718 also includes sixtorque-transmitting mechanisms 750, 752, 754, 756, 758 and 759. Thetorque-transmitting mechanisms 750, 752, 754 and 756 are rotating typetorque-transmitting mechanisms, commonly termed clutches. Thetorque-transmitting mechanisms 758 and 759 are stationary-typetorque-transmitting mechanisms, commonly termed brakes or reactionclutches.

[0157] The input shaft 17 is continuously connected with the sun gearmember 742, and the output shaft 19 is continuously connected with thering gear member 734. The planet carrier assembly member 726 iscontinuously connected with the transmission housing 760. The sun gearmember 722 is continuously connected with the sun gear member 732 andthe ring gear member 744 through the interconnecting member 770.

[0158] The ring gear member 724 is selectively connectable with theplanet carrier assembly member 746 through the clutch 750. The planetcarrier assembly member 736 is selectively connectable with the sun gearmember 732 through the clutch 752. The planet carrier assembly member736 is selectively connectable with the planet carrier assembly member746 through the clutch 754. The planet carrier assembly member 736 isselectively connectable with the sun gear member 742 through the clutch756. The sun gear member 722 is selectively connectable with thetransmission housing 760 through the brake 758. The planet carrierassembly member 736 is selectively connectable with the transmissionhousing 760 through the brake 759.

[0159] The truth table of FIG. 8b defines the torque-transmittingmechanism engagement sequence utilized for each of the forward speedratios and the reverse speed ratio. Also given in the truth table is aset of numerical values that are attainable with the present inventionutilizing the ring gear/sun gear tooth ratios given in FIG. 8b. TheR1/S1 value is the tooth ratio of the planetary gear set 720; the R2/S2value is the tooth ratio of the planetary gear set 730; and the R3/S3value is the tooth ratio of the planetary gear set 740. As can also bedetermined from the truth table of FIG. 8b, the single step forwardinterchanges are single transition shifts, as are the double stepinterchanges in the forward direction.

[0160]FIG. 8b also provides a chart of the ratio steps between adjacentforward ratios and between the reverse and first forward ratio. Forexample, the ratio step between the first and second forward ratios is1.72. Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 720 and 740. The numericalvalues of the first, third and seventh forward speed ratios aredetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 720, 730 and 740. The numerical values of the secondand fourth forward speed ratios are determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 730 and 740. Thenumerical value of the fifth forward speed ratio is 1. The numericalvalue of the sixth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratio of the planetary gear set 730.

[0161] A powertrain 810, shown in FIG. 9a, has the conventional engineand torque converter 12, a planetary transmission 814, and the finaldrive mechanism 16. The engine and torque converter 12 are drivinglyconnected with the planetary transmission 814 through the input shaft17. The planetary transmission 814 is drivingly connected with the finaldrive mechanism 16 through the output shaft 19. The planetarytransmission 814 includes a planetary gear arrangement 818 that has afirst planetary gear set 820, a second planetary gear set 830, and athird planetary gear set 840.

[0162] The planetary gear set 820 includes a sun gear member 822, a ringgear member 824, and a planet carrier assembly 826. The planet carrierassembly 826 includes a plurality of pinion gears 827 rotatably mountedon a carrier member 829 and disposed in meshing relationship with boththe sun gear member 822 and the ring gear member 824.

[0163] The planetary gear set 830 includes a sun gear member 832, a ringgear member 834, and a planet carrier assembly member 836. The planetcarrier assembly member 836 includes a plurality of pinion gears 837rotatably mounted on a carrier member 839 and disposed in meshingrelationship with both the sun gear member 832 and the ring gear member834.

[0164] The planetary gear set 840 includes a sun gear member 842, a ringgear member 844, and a planet carrier assembly member 846. The planetcarrier assembly member 846 includes a plurality of pinion gears 847rotatably mounted on a carrier member 849 and disposed in meshingrelationship with both the sun gear member 842 and the ring gear member844.

[0165] The planetary gear arrangement 818 also includes sixtorque-transmitting mechanisms 850, 852, 854, 856, 858 and 859. Thetorque-transmitting mechanisms 850, 852, 854, 856 and 858 are rotatingtype torque-transmitting mechanisms, commonly termed clutches. Thetorque-transmitting mechanism 859 is a stationary-typetorque-transmitting mechanism, commonly termed brake or reaction clutch.

[0166] The input shaft 17 is continuously connected with the sun gearmember 832, and the output shaft 19 is continuously connected with thering gear member 844. The sun gear member 822 is continuously connectedwith the transmission housing 860. The planet carrier assembly member826 is continuously connected with the ring gear member 834 and the sungear member 842 through the interconnecting member 870.

[0167] The ring gear member 824 is selectively connectable with theplanet carrier assembly member 826 through the clutch 850. The ring gearmember 824 is selectively connectable with the planet carrier assemblymember 836 through the clutch 852. The ring gear member 824 isselectively connectable with the sun gear member 832 through the clutch854. The planet carrier assembly member 836 is selectively connectablewith the planet carrier assembly member 846 through the clutch 856. Thesun gear member 832 is selectively connectable with the planet carrierassembly member 846 through the clutch 858. The planet carrier assemblymember 846 is selectively connectable with the transmission housing 860through the brake 859.

[0168] The truth table shown in FIG. 9b defines the torque-transmittingmechanism engagement sequence that provides the reverse speed ratio andeight forward speed ratios shown in the truth table and available withthe planetary gear arrangement 818. The truth table indicates that thetorque-transmitting mechanism 859 can remain engaged through the neutralcondition, thereby simplifying the forward/reverse interchange. A sampleof numerical values for the individual ratios is also given in the truthtable of FIG. 9b. These numerical values have been calculated using thering gear/sun gear tooth ratios also given by way of example in FIG. 9b.The R1/S1 value is the tooth ratio of the planetary gear set 820; theR2/S2 value is the tooth ratio of the planetary gear set 830; and theR3/S3 value is the tooth ratio of the planetary gear set 840. It can bereadily recognized from the truth table that all of the single anddouble step forward interchanges are single transition ratiointerchanges. FIG. 9b also describes the ratio steps between adjacentforward ratios and between the reverse and first forward ratio. Forexample, the ratio step between the first and second forward ratios is2.18.

[0169] Those skilled in the art of planetary transmissions willrecognize that the numerical values of the reverse and sixth forwardspeed ratios are determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 820 and 840. The numerical values ofthe first and second forward speed ratios are determined utilizing thering gear/sun gear tooth ratios of the planetary gear sets 830 and 840.The numerical values of the third, fourth and seventh forward speedratios are determined utilizing the ring gear/sun gear tooth ratios ofthe planetary gear sets 820, 830 and 840. The numerical value of thefifth forward speed ratio is 1. The numerical value of the eighthforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 840.

[0170] The powertrain 910, shown in FIG. 10a, includes the conventionalengine and torque converter 12, a planetary transmission 914, and theconventional final drive mechanism 16. The engine and torque converter12 are drivingly connected with the planetary transmission 914 throughthe input shaft 17. The planetary transmission 914 is drivinglyconnected with the final drive mechanism 16 through the output shaft 19.The planetary transmission 914 includes a planetary gear arrangement 918that has a first planetary gear set 920, a second planetary gear set930, and a third planetary gear set 940.

[0171] The planetary gear set 920 includes a sun gear member 922, a ringgear member 924, and a planet carrier assembly 926. The planet carrierassembly 926 includes a plurality of pinion gears 927 that are rotatablymounted on a carrier member 929 and disposed in meshing relationshipwith the sun gear member 922 and the ring gear member 924, respectively.

[0172] The planetary gear set 930 includes a sun gear member 932, a ringgear member 934, and a planet carrier assembly member 936. The planetcarrier assembly member 936 includes a plurality of pinion gears 937rotatably mounted on a carrier member 939 and disposed in meshingrelationship with both the sun gear member 932 and the ring gear member934.

[0173] The planetary gear set 940 includes a sun gear member 942, a ringgear member 944, and a planet carrier assembly member 946. The planetcarrier assembly member 946 includes a plurality of pinion gears 947rotatably mounted on a carrier member 949 and disposed in meshingrelationship with both the sun gear member 942 and the ring gear member944.

[0174] The planetary gear arrangement 918 also includes sixtorque-transmitting mechanisms 950, 952, 954, 956, 958 and 959. Thetorque-transmitting mechanisms 950, 952, 954, 956 and 958 are rotatingtype torque-transmitting mechanisms, commonly termed clutches. Thetorque-transmitting mechanism 959 is a stationary-typetorque-transmitting mechanism, commonly termed brake or reaction clutch.

[0175] The input shaft 17 is continuously connected with the sun gearmember 942, and the output shaft 19 is continuously connected with thering gear member 934. The planet carrier assembly member 926 iscontinuously connected with the transmission housing 960. The sun gearmember 922 is continuously connected with the sun gear member 932 andthe ring gear member 944 through the interconnecting member 970.

[0176] The ring gear member 924 is selectively connectable with the sungear member 922 through the clutch 950. The ring gear member 924 isselectively connectable with the planet carrier assembly member 946through the clutch 952. The planet carrier assembly member 936 isselectively connectable with the sun gear member 932 through the clutch954. The planet carrier assembly member 936 is selectively connectablewith the planet carrier assembly member 946 through the clutch 956. Theplanet carrier assembly member 936 is selectively connectable with thesun gear member 942 through the clutch 958. The planet carrier assemblymember 936 is selectively connectable with the transmission housing 960through the brake 959.

[0177] The truth table of FIG. 10b describes the torque-transmittingmechanism engagement sequence utilized to provide the reverse speedratio and seven forward speed ratios. The truth table also provides aset of examples for the ratios for each of the reverse and forward speedratios. These numerical values have been determined utilizing the ringgear/sun gear tooth ratios given in FIG. 10b. The R1/S1 value is thetooth ratio of the planetary gear set 920; the R2/S2 value is the toothratio of the planetary gear set 930; and the R3/S3 value is the toothratio of the planetary gear set 940. It can also be determined from thetruth table of FIG. 10b that each of the forward single and double stepratio interchanges are of the single transition variety.

[0178] Those skilled in the art, upon reviewing the engagementcombinations, will recognize that the numerical value of the reversespeed ratio is determined utilizing the ring gear/sun gear tooth ratiosof the planetary gear sets 920 and 940. The numerical values of thefirst, third and seventh forward speed ratios are determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 920, 930and 940. The numerical values of the second and fourth forward speedratios are determined utilizing the ring gear/sun gear tooth ratios ofthe planetary gear sets 930 and 940. The numerical value of the fifthforward speed ratio is 1. The numerical value of the sixth forward speedratio is determined utilizing the ring gear/sun gear tooth ratio of theplanetary gear set 930.

[0179] A powertrain 1010, shown in FIG. 11a, includes the conventionalengine and torque converter 12, a planetary transmission 1014, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1014 through theinput shaft 17. The planetary transmission 1014 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1014 includes a planetary gear arrangement 1018that has a first planetary gear set 1020, a second planetary gear set1030, and a third planetary gear set 1040.

[0180] The planetary gear set 1020 includes a sun gear member 1022, aring gear member 1024, and a planet carrier assembly 1026. The planetcarrier assembly 1026 includes a plurality of pinion gears 1027rotatably mounted on a carrier member 1029 and disposed in meshingrelationship with both the sun gear member 1022 and the ring gear member1024.

[0181] The planetary gear set 1030 includes a sun gear member 1032, aring gear member 1034, and a planet carrier assembly member 1036. Theplanet carrier assembly member 1036 includes a plurality of pinion gears1037 rotatably mounted on a carrier member 1039 and disposed in meshingrelationship with both the sun gear member 1032 and the ring gear member1034.

[0182] The planetary gear set 1040 includes a sun gear member 1042, aring gear member 1044, and a planet carrier assembly member 1046. Theplanet carrier assembly member 1046 includes a plurality of pinion gears1047 rotatably mounted on a carrier member 1049 and disposed in meshingrelationship with both the sun gear member 1042 and the ring gear member1044.

[0183] The planetary gear arrangement 1018 also includes sixtorque-transmitting mechanisms 1050, 1052, 1054, 1056, 1058 and 1059.The torque-transmitting mechanisms 1050, 1052, 1054, 1056 and 1058 arerotating type torque-transmitting mechanisms, commonly termed clutches.The torque-transmitting mechanism 1059 is a stationary-typetorque-transmitting mechanism, commonly termed brake or reaction clutch.

[0184] The input shaft 17 is continuously connected with the ring gearmember 1044, and the output shaft 19 is continuously connected with theplanet carrier assembly member 1036. The ring gear member 1024 iscontinuously connected with the transmission housing 1060. The sun gearmember 1022 is continuously connected with the ring gear member 1034 andthe sun gear member 1042 through the interconnecting member 1070.

[0185] The planet carrier assembly member 1026 is selectivelyconnectable with the planet carrier assembly member 1036 through theclutch 1050. The planet carrier assembly member 1026 is selectivelyconnectable with the ring gear member 1044 through the clutch 1052. Theplanet carrier assembly member 1036 is selectively connectable with theplanet carrier assembly member 1046 through the clutch 1054. The sungear member 1032 is selectively connectable with the planet carrierassembly member 1046 through the clutch 1056. The ring gear member 1044is selectively connectable with the sun gear member 1032 through theclutch 1058. The planet carrier assembly member 1026 is selectivelyconnectable with the transmission housing 1060 through the brake 1059.

[0186] The truth table shown in FIG. 11b describes the engagementcombinations and the engagement sequence necessary to provide thereverse drive ratio and the eight forward speed ratios. A sample of thenumerical values for the ratios is also provided in the truth table ofFIG. 11b. These values are determined utilizing the ring gear/sun geartooth ratios also given in FIG. 11b. The R1/S1 value is the tooth ratiofor the planetary gear set 1020; the R2/S2 value is the tooth ratio forthe planetary gear set 1030; and the R3/S3 value is the tooth ratio forthe planetary gear set 1040. Also given in FIG. 11b is a chartdescribing the step ratios between the adjacent forward speed ratios andthe reverse to first forward speed ratio.

[0187] Those skilled in the art will recognize that the numerical valuesof the reverse and sixth forward speed ratios are determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 1020 and1030. The numerical values of the first and fifth forward speed ratiosare determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 1030 and 1040. The numerical value of the secondforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 1030. The numerical value of the thirdforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 1040. The numerical value of the fourthforward speed ratio is 1. The numerical value of the seventh forwardspeed ratio is determined utilizing the ring gear/sun gear tooth ratiosof the planetary gear sets 1020, 1030 and 1040. The numerical value ofthe eighth forward speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 1020 and 1040.

[0188] A powertrain 1110, shown in FIG. 12a, has a conventional engineand torque converter 12, a planetary transmission 1114, and theconventional final drive mechanism 16. The planetary transmission 1114includes a planetary gear arrangement 1118 which is connected with theengine and torque converter 12 through the input shaft 17 and with thefinal drive mechanism 16 through the output shaft 19. The planetary geararrangement 1118 includes three planetary gear sets 1120, 1130 and 1140.

[0189] The planetary gear set 1120 includes a sun gear member 1122, aring gear member 1124, and a planet carrier assembly 1126. The planetcarrier assembly 1126 includes a plurality of pinion gears 1127rotatably mounted on a carrier member 1129 and disposed in meshingrelationship with both the sun gear member 1122 and the ring gear member1124.

[0190] The planetary gear set 1130 includes a sun gear member 1132, aring gear member 1134, and a planet carrier assembly member 1136. Theplanet carrier assembly member 1136 includes a plurality of intermeshingpinion gears 1137 that are rotatably mounted on a carrier member 1139and disposed in meshing relationship with both the sun gear member 1132and the ring gear member 1134.

[0191] The planetary gear set 1140 includes a sun gear member 1142, aring gear member 1144, and a planet carrier assembly member 1146. Theplanet carrier assembly member 1146 includes a plurality of pinion gears1147 rotatably mounted on a carrier member 1149 and disposed in meshingrelationship with both the sun gear member 1142 and the ring gear member1144.

[0192] The planetary gear arrangement 1118 also includes sixtorque-transmitting mechanisms 1150, 1152, 1154, 1156, 1158 and 1159.The torque-transmitting mechanisms 1150, 1152, 1154, 1156 and 1158 arerotating type torque-transmitting mechanisms, commonly termed clutches.The torque-transmitting mechanism 1159 is a stationary-typetorque-transmitting mechanism, commonly termed brake or reaction clutch.

[0193] The input shaft 17 is continuously connected with the sun gearmember 1142, and the output shaft 19 is continuously connected with thering gear member 1134. The planet carrier assembly member 1126 iscontinuously connected with the transmission housing 1160. The sun gearmember 1122 is continuously connected with the sun gear member 1132 andthe ring gear member 1144 through the interconnecting member 1170.

[0194] The ring gear member 1124 is selectively connectable with the sungear member 1122 through the clutch 1150. The ring gear member 1124 isselectively connectable with the planet carrier assembly member 1146through the clutch 1152. The sun gear member 1122 is selectivelyconnectable with the planet carrier assembly member 1136 through theclutch 1154. The planet carrier assembly member 1136 is selectivelyconnectable with the planet carrier assembly member 1146 through theclutch 1156. The planet carrier assembly member 1136 is selectivelyconnectable with the sun gear member 1146 through the clutch 1158. Theplanet carrier assembly member 1146 is selectively connectable with thetransmission housing 1160 through the brake 1159.

[0195] The truth table shown in FIG. 12b describes the engagementsequence and engagement combinations utilized with the present familymember to provide the reverse drive ratio and seven forward speedratios. The truth table of FIG. 12b also provides a set of examplenumbers that can be established in the planetary gear arrangement 1118utilizing the ring gear/sun gear tooth ratios. The R1/S1 value is thering gear/sun gear tooth ratio of the planetary gear set 1120; the R2/S2value is the ring gear/sun gear tooth ratio of the planetary gear set1130; and the R3/S3 value is the ring gear/sun gear tooth ratio of theplanetary gear set 1140.

[0196] The chart of FIG. 12b describes the ratio steps between adjacentforward speed ratios for a seven-speed transmission. These step ratiosare established utilizing the example speed ratios given in the truthtable.

[0197] Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratio of the planetary gear set 1140. The numerical values ofthe first, third and seventh forward speed ratios are determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets1130 and 1140. The numerical values of the second and sixth forwardspeed ratios are determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 1120, 1130 and 1140. The numericalvalue of the fourth forward speed ratio is 1. The numerical value of thefifth forward speed ratio is determined utilizing the ring gear/sun geartooth ratio of the planetary gear set 1130.

[0198] A powertrain 1210, shown in FIG. 13a, includes the conventionalengine and torque converter 12, a planetary transmission 1214, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1214 through theinput shaft 17. The planetary transmission 1214 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1214 includes a planetary gear arrangement 1218that has a first planetary gear set 1220, a second planetary gear set1230, and a third planetary gear set 1240.

[0199] The planetary gear set 1220 includes a sun gear member 1222, aring gear member 1224, and a planet carrier assembly 1226. The planetcarrier assembly 1226 includes a plurality of pinion gears 1227rotatably mounted on a carrier member 1229 and disposed in meshingrelationship with both the sun gear member 1222 and the ring gear member1224.

[0200] The planetary gear set 1230 includes a sun gear member 1232, aring gear member 1234, and a planet carrier assembly member 1236. Theplanet carrier assembly member 1236 includes a plurality of pinion gears1237 rotatably mounted on a carrier member 1239 and disposed in meshingrelationship with both the sun gear member 1232 and the ring gear member1234.

[0201] The planetary gear set 1240 includes a sun gear member 1242, aring gear member 1244, and a planet carrier assembly member 1246. Theplanet carrier assembly member 1246 includes a plurality of pinion gears1247 rotatably mounted on a carrier member 1249 and disposed in meshingrelationship with both the sun gear member 1242 and the ring gear member1244.

[0202] The planetary gear arrangement 1218 also includes sixtorque-transmitting mechanisms 1250, 1252, 1254, 1256, 1258 and 1259.The torque-transmitting mechanisms 1250, 1252, 1254, 1256 and 1258 arerotating type torque-transmitting mechanisms, commonly termed clutches.The torque-transmitting mechanism 1259 is a stationary-typetorque-transmitting mechanism, commonly termed brake or reaction clutch.

[0203] The input shaft 17 is continuously connected with the ring gearmember 1234, and the output shaft 19 is continuously connected with theplanet carrier assembly member 1246. The sun gear member 1222 iscontinuously connected with the transmission housing 1260. The planetcarrier assembly member 1226 is continuously connected with the planetcarrier assembly member 1236 and the ring gear member 1244 through theinterconnecting member 1270.

[0204] The ring gear member 1224 is selectively connectable with the sungear member 1232 through the clutch 1250. The ring gear member 1224 isselectively connectable with the planet carrier assembly member 1246through the clutch 1252. The ring gear member 1224 is selectivelyconnectable with the sun gear member 1242 through the clutch 1254. Thesun gear member 1232 is selectively connectable with the sun gear member1242 through the clutch 1256. The ring gear member 1234 is selectivelyconnectable with the sun gear member 1242 through the clutch 1258. Theplanet carrier assembly member 1226 is selectively connectable with thetransmission housing 1260 through the brake 1259.

[0205] The truth table shown in FIG. 13b describes the engagementcombinations and the engagement sequence necessary to provide a reversespeed ratio and seven forward speed ratios. A sample of the numericalvalues for the ratios is also provided in the truth table of FIG. 13b.These values are determined utilizing the ring gear/sun gear toothratios also given in FIG. 13b. The R1/S1 value is the tooth ratio forthe planetary gear set 1220; the R2/S2 value is the tooth ratio for theplanetary gear set 1230; and the R3/S3 value is the tooth ratio for theplanetary gear set 1240. Also given in FIG. 13b is a chart describingthe step ratios between the adjacent forward speed ratios and thereverse to first forward speed ratio.

[0206] Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 1230 and 1240. Thenumerical value of the first forward speed ratio is determined utilizingthe ring gear/sun gear tooth ratio of the planetary gear set 1240. Thenumerical values of the second and third forward speed ratios aredetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 1220 and 1240. The numerical value of the fourthforward speed ratio is 1. The numerical values of the fifth and sixthforward speed ratios are determined utilizing the ring gear/sun geartooth ratios of the planetary gear sets 1220, 1230 and 1240. Thenumerical value of the seventh forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets1220 and 1230.

[0207] A powertrain 1310, shown in FIG. 14a, includes the conventionalengine and torque converter 12, a planetary transmission 1314, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1314 through theinput shaft 17. The planetary transmission 1314 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1314 includes a planetary gear arrangement 1318that has a first planetary gear set 1320, a second planetary gear set1330, and a third planetary gear set 1340.

[0208] The planetary gear set 1320 includes a sun gear member 1322, aring gear member 1324, and a planet carrier assembly 1326. The planetcarrier assembly 1326 includes a plurality of pinion gears 1327rotatably mounted on a carrier member 1329 and disposed in meshingrelationship with both the sun gear member 1322 and the ring gear member1324.

[0209] The planetary gear set 1330 includes a sun gear member 1332, aring gear member 1334, and a planet carrier assembly member 1336. Theplanet carrier assembly member 1336 includes a plurality of pinion gears1337 rotatably mounted on a carrier member 1339 and disposed in meshingrelationship with both the sun gear member 1332 and the ring gear member1334.

[0210] The planetary gear set 1340 includes a sun gear member 1342, aring gear member 1344, and a planet carrier assembly member 1346. Theplanet carrier assembly member 1346 includes a plurality of pinion gears1347 rotatably mounted on a carrier member 1349 and disposed in meshingrelationship with both the sun gear member 1342 and the ring gear member1344.

[0211] The planetary gear arrangement 1318 also includes sixtorque-transmitting mechanisms 1350, 1352, 1354, 1356, 1358 and 1359.The torque-transmitting mechanisms 1350, 1352, 1354, 1356 and 1358 arerotating type torque-transmitting mechanisms, commonly termed clutches.The torque-transmitting mechanism 1359 is a stationary-typetorque-transmitting mechanism, commonly termed brake or reaction clutch.

[0212] The input shaft 17 is continuously connected with the sun gearmember 1332, and the output shaft 19 is continuously connected with thering gear member 1344. The sun gear member 1322 is continuouslyconnected with the transmission housing 1360. The ring gear member 1324is continuously connected with the ring gear member 1334 and the sungear member 1342 through the interconnecting member 1370.

[0213] The ring gear member 1324 is selectively connectable with theplanet carrier assembly member 1326 through the clutch 1350. The planetcarrier assembly member 1326 is selectively connectable with the planetcarrier assembly member 1336 through the clutch 1352. The planet carrierassembly member 1326 is selectively connectable with the ring gearmember 1344 through the clutch 1354. The ring gear member 1344 isselectively connectable with the sun gear member 1342 through the clutch1356. The planet carrier assembly member 1336 is selectively connectablewith the planet carrier assembly member 1346 through the clutch 1358.The planet carrier assembly member 1336 is selectively connectable withthe transmission housing 1360 through the brake 1359.

[0214] The truth table shown in FIG. 14b describes the engagementcombinations and the engagement sequence necessary to provide thereverse drive ratio and seven forward speed ratios. A sample of thenumerical values for the ratios is also provided in the truth table ofFIG. 14b. These values are determined utilizing the ring gear/sun geartooth ratios also given in FIG. 14b. The R1/S1 value is the tooth ratiofor the planetary gear set 1320; the R2/S2 value is the tooth ratio forthe planetary gear set 1330; and the R3/S3 value is the tooth ratio forthe planetary gear set 1340. Also given in FIG. 14b is a chartdescribing the step ratios between the adjacent forward speed ratios andthe reverse to first forward speed ratio.

[0215] Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratio of the planetary gear set 1330. The numerical values ofthe first and second forward speed ratios are determined utilizing thering gear/sun gear tooth ratios of the planetary gear sets 1330 and1340. The numerical value of the third forward speed ratio is 1. Thenumerical values of the fourth and fifth forward speed ratios aredetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 1320, 1330 and 1340. The numerical values of thesixth and seventh forward speed ratios are determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 1320 and 1330.

[0216] A powertrain 1410, shown in FIG. 15a, includes the conventionalengine and torque converter 12, a planetary transmission 1414, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1414 through theinput shaft 17. The planetary transmission 1414 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1414 includes a planetary gear arrangement 1418that has a first planetary gear set 1420, a second planetary gear set1430, and a third planetary gear set 1440.

[0217] The planetary gear set 1420 includes a sun gear member 1422, aring gear member 1424, and a planet carrier assembly 1426. The planetcarrier assembly 1426 includes a plurality of pinion gears 1427rotatably mounted on a carrier member 1429 and disposed in meshingrelationship with both the sun gear member 1422 and the ring gear member1424.

[0218] The planetary gear set 1430 includes a sun gear member 1432, aring gear member 1434, and a planet carrier assembly member 1436. Theplanet carrier assembly member 1436 includes a plurality of pinion gears1437 rotatably mounted on a carrier member 1439 and disposed in meshingrelationship with both the sun gear member 1432 and the ring gear member1434.

[0219] The planetary gear set 1440 includes a sun gear member 1442, aring gear member 1444, and a planet carrier assembly member 1446. Theplanet carrier assembly member 1446 includes a plurality of pinion gears1447 rotatably mounted on a carrier member 1449 and disposed in meshingrelationship with both the sun gear member 1442 and the ring gear member1444.

[0220] The planetary gear arrangement 1418 also includes sixtorque-transmitting mechanisms 1450, 1452, 1454, 1456, 1458 and 1459.The torque-transmitting mechanisms 1450, 1452, 1454, 1456 and 1458 arerotating type torque-transmitting mechanisms, commonly termed clutches.The torque-transmitting mechanism 1459 is a stationary-typetorque-transmitting mechanism, commonly termed brake or reaction clutch.

[0221] The input shaft 17 is continuously connected with the sun gearmember 1442, and the output shaft 19 is continuously connected with theplanet carrier assembly member 1436. The sun gear member 1422 iscontinuously connected with the transmission housing 1460. The ring gearmember 1424 is continuously connected with the sun gear member 1432 andthe ring gear member 1444 through the interconnecting member 1470.

[0222] The ring gear member 1424 is selectively connectable with theplanet carrier assembly member 1426 through the clutch 1450. The planetcarrier assembly member 1426 is selectively connectable with the planetcarrier assembly member 1436 through the clutch 1452. The planet carrierassembly member 1426 is selectively connectable with the planet carrierassembly member 1446 through the clutch 1454. The ring gear member 1434is selectively connectable with the sun gear member 1432 through theclutch 1456. The ring gear member 1434 is selectively connectable withthe sun gear member 1442 through the clutch 1458. The planet carrierassembly member 1446 is selectively connectable with the transmissionhousing 1460 through the brake 1459.

[0223] The truth table shown in FIG. 15b describes the engagementcombinations and the engagement sequence necessary to provide thereverse drive ratio and seven forward speed ratios. A sample of thenumerical values for the ratios is also provided in the truth table ofFIG. 15b. These values are determined utilizing the ring gear/sun geartooth ratios also given in FIG. 15b. The R1/S1 value is the tooth ratiofor the planetary gear set 1420; the R2/S2 value is the tooth ratio forthe planetary gear set 1430; and the R3/S3 value is the tooth ratio forthe planetary gear set 1440. Also given in FIG. 15b is a chartdescribing the step ratios between the adjacent forward speed ratios andthe reverse to first forward speed ratio.

[0224] Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratio of the planetary gear set 1440. The numerical value ofthe first forward speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 1430 and 1440. Thenumerical value of the second forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratio of the planetary gear set1430. The numerical value of the third forward speed ratio is 1. Thenumerical value of the fourth forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets1420 and 1430. The numerical value of the fifth forward speed ratio isdetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 1420, 1430 and 1440. The numerical values of thesixth and seventh forward speed ratios are determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 1420 and 1440.

[0225] A powertrain 1510, shown in FIG. 16a, includes the conventionalengine and torque converter 12, a planetary transmission 1514, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1514 through theinput shaft 17. The planetary transmission 1514 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1514 includes a planetary gear arrangement 1518that has a first planetary gear set 1520, a second planetary gear set1530, and a third planetary gear set 1540.

[0226] The planetary gear set 1520 includes a sun gear member 1522, aring gear member 1524, and a planet carrier assembly 1526. The planetcarrier assembly 1526 includes a plurality of pinion gears 1527rotatably mounted on a carrier member 1529 and disposed in meshingrelationship with both the sun gear member 1522 and the ring gear member1524.

[0227] The planetary gear set 1530 includes a sun gear member 1532, aring gear member 1534, and a planet carrier assembly member 1536. Theplanet carrier assembly member 1536 includes a plurality of pinion gears1537 rotatably mounted on a carrier member 1539 and disposed in meshingrelationship with both the sun gear member 1532 and the ring gear member1534.

[0228] The planetary gear set 1540 includes a sun gear member 1542, aring gear member 1544, and a planet carrier assembly member 1546. Theplanet carrier assembly member 1546 includes a plurality of pinion gears1547 and 1548 rotatably mounted on a carrier member 1549 and disposed inmeshing relationship with both the sun gear member 1542 and the ringgear member 1544.

[0229] The planetary gear arrangement 1518 also includes sixtorque-transmitting mechanisms 1550, 1552, 1554, 1556, 1558 and 1559,each of which is a rotating type torque-transmitting mechanism, commonlytermed clutch.

[0230] The input shaft 17 is continuously connected with the sun gearmember 1532, and the output shaft 19 is continuously connected with theplanet carrier assembly member 1546. The sun gear member 1522 iscontinuously connected with the transmission housing 1560. The ring gearmember 1524 is continuously connected with the planet carrier assemblymember 1536 and the sun gear member 1542 through the interconnectingmember 1570.

[0231] The ring gear member 1524 is selectively connectable with theplanet carrier assembly member 1526 through the clutch 1550. The planetcarrier assembly member 1526 is selectively connectable with the sungear member 1532 through the clutch 1552. The planet carrier assemblymember 1526 is selectively connectable with the ring gear member 1534through the clutch 1554. The planet carrier assembly member 1546 isselectively connectable with the sun gear member 1542 through the clutch1556. The ring gear member 1534 is selectively connectable with theplanet carrier assembly member 1546 through the clutch 1558. The ringgear member 1534 is selectively connectable with the ring gear member1544 through the clutch 1559.

[0232] The truth table shown in FIG. 16b describes the engagementcombinations and the engagement sequence necessary to provide thereverse drive ratio and the seven forward speed ratios. A sample of thenumerical values for the ratios is also provided in the truth table ofFIG. 16b. These values are determined utilizing the ring gear/sun geartooth ratios also given in FIG. 16b. The R1/S1 value is the tooth ratiofor the planetary gear set 1520; the R2/S2 value is the tooth ratio forthe planetary gear set 1530; and the R3/S3 value is the tooth ratio forthe planetary gear set 1540. Also given in FIG. 16b is a chartdescribing the step ratios between the adjacent forward speed ratios andthe reverse to first forward speed ratio.

[0233] Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 1530 and 1540. Thenumerical values of the first and seventh forward speed ratios aredetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 1520, 1530 and 1540. The numerical values of thesecond, third and sixth forward speed ratios are determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 1520 and1530. The numerical value of the fourth forward speed ratio is 1. Thenumerical value of the fifth forward speed ratio is determined utilizingthe ring gear/sun gear tooth ratio of the planetary gear set 1520.

[0234] A powertrain 1610, shown in FIG. 17a, includes the conventionalengine and torque converter 12, a planetary transmission 1614, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1614 through theinput shaft 17. The planetary transmission 1614 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1614 includes a planetary gear arrangement 1618that has a first planetary gear set 1620, a second planetary gear set1630, and a third planetary gear set 1640.

[0235] The planetary gear set 1620 includes a sun gear member 1622, aring gear member 1624, and a planet carrier assembly 1626. The planetcarrier assembly 1626 includes a plurality of pinion gears 1627rotatably mounted on a carrier member 1629 and disposed in meshingrelationship with both the sun gear member 1622 and the ring gear member1624.

[0236] The planetary gear set 1630 includes a sun gear member 1632, aring gear member 1634, and a planet carrier assembly member 1636. Theplanet carrier assembly member 1636 includes a plurality of pinion gears1637 rotatably mounted on a carrier member 1639 and disposed in meshingrelationship with both the sun gear member 1632 and the ring gear member1634.

[0237] The planetary gear set 1640 includes a sun gear member 1642, aring gear member 1644, and a planet carrier assembly member 1646. Theplanet carrier assembly member 1646 includes a plurality of pinion gears1647 rotatably mounted on a carrier member 1649 and disposed in meshingrelationship with both the sun gear member 1642 and the ring gear member1644.

[0238] The planetary gear arrangement 1618 also includes sixtorque-transmitting mechanisms 1650, 1652, 1654, 1656, 1658 and 1659,each of which is a rotating-type torque-transmitting mechanism, commonlytermed clutch.

[0239] The input shaft 17 is continuously connected with the sun gearmember 1632, and the output shaft 19 is continuously connected with thering gear member 1644. The sun gear member 1622 is continuouslyconnected with the transmission housing 1660. The ring gear member 1624is continuously connected with the planet carrier assembly members 1636and 1646 through the interconnecting member 1670.

[0240] The ring gear member 1624 is selectively connectable with theplanet carrier assembly member 1626 through the clutch 1650. The planetcarrier assembly member 1626 is selectively connectable with the sungear member 1632 through the clutch 1652. The planet carrier assemblymember 1626 is selectively connectable with the ring gear member 1634through the clutch 1654. The ring gear member 1644 is selectivelyconnectable with the planet carrier assembly member 1646 through theclutch 1656. The sun gear member 1632 is selectively connectable withthe sun gear member 1642 through the clutch 1658. The ring gear member1634 is selectively connectable with the ring gear member 1644 throughthe clutch 1659.

[0241] The truth table shown in FIG. 17b describes the engagementcombinations and the engagement sequence necessary to provide thereverse drive ratio and the seven forward speed ratios. A sample of thenumerical values for the ratios is also provided in the truth table ofFIG. 17b. These values are determined utilizing the ring gear/sun geartooth ratios also given in FIG. 17b. The R1/S1 value is the tooth ratiofor the planetary gear set 1620; the R2/S2 value is the tooth ratio forthe planetary gear set 1630; and the R3/S3 value is the tooth ratio forthe planetary gear set 1640. Also given in FIG. 17b is a chartdescribing the step ratios between the adjacent forward speed ratios andthe reverse to first forward speed ratio.

[0242] Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratio of the planetary gear set 1640. The numerical value ofthe first forward speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 1620, 1630 and 1640. Thenumerical values of the second, third and sixth forward speed ratios aredetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 1620 and 1630. The numerical value of the fourthforward speed ratio is 1. The numerical value of the fifth forward speedratio is determined utilizing the ring gear/sun gear tooth ratio of theplanetary gear set 1620. The numerical value of the seventh forwardspeed ratio is determined utilizing the ring gear/sun gear tooth ratiosof the planetary gear sets 1620 and 1640.

[0243] A powertrain 1710, shown in FIG. 18a, includes the conventionalengine and torque converter 12, a planetary transmission 1714, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1714 through theinput shaft 17. The planetary transmission 1714 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1714 includes a planetary gear arrangement 1718that has a first planetary gear set 1720, a second planetary gear set1730, and a third planetary gear set 1740.

[0244] The planetary gear set 1720 includes a sun gear member 1722, aring gear member 1724, and a planet carrier assembly 1726. The planetcarrier assembly 1726 includes a plurality of pinion gears 1727rotatably mounted on a carrier member 1729 and disposed in meshingrelationship with both the sun gear member 1722 and the ring gear member1724.

[0245] The planetary gear set 1730 includes a sun gear member 1732, aring gear member 1734, and a planet carrier assembly member 1736. Theplanet carrier assembly member 1736 includes a plurality of pinion gears1737 rotatably mounted on a carrier member 1739 and disposed in meshingrelationship with both the sun gear member 1732 and the ring gear member1734.

[0246] The planetary gear set 1740 includes a sun gear member 1742, aring gear member 1744, and a planet carrier assembly member 1746. Theplanet carrier assembly member 1746 includes a plurality of pinion gears1747 rotatably mounted on a carrier member 1749 and disposed in meshingrelationship with both the sun gear member 1742 and the ring gear member1744.

[0247] The planetary gear arrangement 1718 also includes sixtorque-transmitting mechanisms 1750, 1752, 1754, 1756, 1758 and 1759,each of which is a rotating-type torque-transmitting mechanism, commonlytermed clutch.

[0248] The input shaft 17 is continuously connected with the sun gearmember 1742, and the output shaft 19 is continuously connected with theplanet carrier assembly member 1736. The ring gear member 1724 iscontinuously connected with the transmission housing 1760. The sun gearmember 1722 is continuously connected with the sun gear member 1732 andthe ring gear member 1744 through the interconnecting member 1770.

[0249] The planet carrier assembly member 1726 is selectivelyconnectable with the sun gear member 1722 through the clutch 1750. Theplanet carrier assembly member 1726 is selectively connectable with theplanet carrier assembly member 1736 through the clutch 1752. The planetcarrier assembly member 1726 is selectively connectable with the sungear member 1742 through the clutch 1754. The planet carrier assemblymember 1736 is selectively connectable with the planet carrier assemblymember 1746 through the clutch 1756. The ring gear member 1734 isselectively connectable with the planet carrier assembly member 1746through the clutch 1758. The ring gear member 1734 is selectivelyconnectable with the sun gear member 1742 through the clutch 1759.

[0250] The truth table shown in FIG. 18b describes the engagementcombinations and the engagement sequence necessary to provide thereverse drive ratio and seven forward speed ratios. A sample of thenumerical values for the ratios is also provided in the truth table ofFIG. 18b. These values are determined utilizing the ring gear/sun geartooth ratios also given in FIG. 18b. The R1/S1 value is the tooth ratiofor the planetary gear set 1720; the R2/S2 value is the tooth ratio forthe planetary gear set 1730; and the R3/S3 value is the tooth ratio forthe planetary gear set 1740. Also given in FIG. 18b is a chartdescribing the step ratios between the adjacent forward speed ratios andthe reverse to first forward speed ratio.

[0251] Those skilled in the art will recognize that the numerical valuesof the reverse and sixth forward speed ratios are determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 1720 and1740. The numerical value of the first forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets1730 and 1740. The numerical value of the second forward speed ratio isdetermined utilizing the ring gear/sun gear tooth ratio of the planetarygear set 1740. The numerical value of the third forward speed ratio isdetermined utilizing the ring gear/sun gear tooth ratio of the planetarygear set 1730. The numerical value of the fourth forward speed ratiois 1. The numerical value of the fifth forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets1720 and 1730. The numerical value of the seventh forward speed ratio isdetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 1720, 1730 and 1740.

[0252] While the best modes for carrying out the invention have beendescribed in detail, those familiar with the art to which this inventionrelates will recognize various alternative designs and embodiments forpracticing the invention within the scope of the appended claims.

1. A family of transmissions wherein each family member comprises: aninput shaft; an output shaft; first, second and third planetary gearsets each having first, second and third members; said input shaft beingcontinuously interconnected with a member of said planetary gear sets,and said output shaft being continuously interconnected with anothermember of said planetary gear sets; an interconnecting membercontinuously interconnecting said first member of said first planetarygear set with said first member of said second planetary gear set andsaid first member of said third planetary gear set; said second memberof said first planetary gear set being continuously connected with astationary member; a first torque-transmitting mechanism selectivelyinterconnecting a member of said first planetary gear set or saidinterconnecting member with said input shaft, said output shaft or amember of said second or third planetary gear set; a secondtorque-transmitting mechanism selectively interconnecting a member ofsaid second planetary gear set or said interconnecting member with saidinput shaft, said output shaft or a member of said first or thirdplanetary gear set; a third torque-transmitting mechanism selectivelyinterconnecting a member of said third planetary gear set or saidinterconnecting member with said input shaft, said output shaft, or amember of said first or second planetary gear set; a fourthtorque-transmitting mechanism selectively interconnecting a member ofsaid first, second or third planetary gear set with another member ofsaid first, second or third planetary gear set or with said stationarymember; a fifth torque-transmitting mechanism selectivelyinterconnecting a member of said first, second or third planetary gearset with another member of said second or third planetary gear set, saidinterconnecting member, or said stationary member; and a sixthtorque-transmitting mechanism selectively interconnecting a member ofthe first, second or third planetary gear set with another member ofsaid first, second or third planetary gear set, said interconnectingmember, or said stationary member; said torque-transmitting mechanismsbeing engaged in combinations of two to establish at least seven forwardspeed ratios and at least one reverse speed ratio between said inputshaft and said output shaft.
 2. The family of transmissions defined inclaim 1, wherein said first, second, third, fourth, fifth and sixthtorque-transmitting mechanisms comprise clutches.
 3. The family oftransmissions defined in claim 1, wherein said first, second, third,fourth and fifth torque-transmitting mechanisms comprise clutches, andsaid sixth torque-transmitting mechanism comprises a brake.
 4. Thefamily of transmissions defined in claim 1, wherein said first, secondand third torque-transmitting mechanisms comprise clutches, and saidfourth, fifth and sixth torque-transmitting mechanisms comprise brakes.5. The family of transmissions defined in claim 1, wherein said first,second, third and fourth torque-transmitting mechanisms compriseclutches, and said fifth and sixth torque-transmitting mechanismscomprise brakes.
 6. The family of transmissions defined in claim 1,wherein planet carrier assembly members of each of said planetary gearsets are of the single-pinion type.
 7. The family of transmissionsdefined in claim 1, wherein at least one planet carrier assembly memberof said planetary gear sets is of the double-pinion type.
 8. A family oftransmissions having a plurality of family members wherein each familymember comprises: an input shaft; an output shaft; a planetary geararrangement having first, second and third planetary gear sets, eachplanetary gear set having first, second and third members; said inputshaft being continuously interconnected with a member of said planetarygear sets, and said output shaft being continuously interconnected withanother member of said planetary gear sets; an interconnecting membercontinuously interconnecting said first member of said first planetarygear set with said first member of said second planetary gear set andsaid first member of said third planetary gear set; said second memberof said first planetary gear set being continuously connected with astationary member; and six torque-transmitting mechanisms forselectively interconnecting said members of said first, second or thirdplanetary gear sets with said input shaft, said output shaft, saidinterconnecting member, said stationary member or with other members ofsaid planetary gear sets, said six torque-transmitting mechanisms beingengaged in combinations of two to establish at least seven forward speedratios and one reverse speed ratio between said input shaft and saidoutput shaft.
 9. The family of transmissions defined in claim 8, whereina first of said six torque-transmitting mechanisms is operable forselectively interconnecting a member of said first planetary gear set orsaid interconnecting member with said input shaft, said output shaft, ora member of said second or third planetary gear set.
 10. The family oftransmissions defined in claim 8, wherein a second of said sixtorque-transmitting mechanisms is operable for selectivelyinterconnecting a member of said second planetary gear set or saidinterconnecting member with said input shaft, said output shaft or amember of said first or third planetary gear set.
 11. The family oftransmissions defined in claim 8, wherein a third of said sixtorque-transmitting mechanisms is operable for selectivelyinterconnecting a member of said third planetary gear set or saidinterconnecting member with said input shaft, said output shaft, or amember of said first or second planetary gear set.
 12. The family oftransmissions defined in claim 8, wherein a fourth of said sixtorque-transmitting mechanisms is selectively operable forinterconnecting a member of said first, second or third planetary gearset with another member of said first, second or third planetary gearset.
 13. The family of transmissions defined in claim 8, wherein afourth of said six torque-transmitting mechanisms is selectivelyoperable for interconnecting a member of said first, second or thirdplanetary gear set with said stationary member.
 14. The family oftransmissions defined in claim 8, wherein a fifth of said sixtorque-transmitting mechanisms is selectively operable forinterconnecting a member of said second or third planetary gear set orsaid interconnecting member with another member of said first, second orthird planetary gear set.
 15. The family of transmissions defined inclaim 8, wherein a fifth of said six torque-transmitting mechanisms isselectively operable for interconnecting a member of said first, secondor third planetary gear set with said stationary member.
 16. The familyof transmissions defined in claim 8, wherein a sixth of said sixtorque-transmitting mechanisms is selectively operable forinterconnecting a member of said first, second or third planetary gearset or said interconnecting member with another member of said first,second or third planetary gear set.
 17. The family of transmissionsdefined in claim 8, wherein a sixth of said six torque-transmittingmechanisms is selectively operable for interconnecting a member of saidfirst, second or third planetary gear set with said stationary member.18. The family of transmissions defined in claim 8, wherein planetcarrier assembly members of each of said planetary gear sets are of thesingle-pinion type.
 19. The family of transmissions in claim 8, whereinat least one planet carrier assembly member of said planetary gear setsis of the double-pinion type.